arm: [MVE intrinsics] rework vstr_scatter_shifted_offset

arm: [MVE intrinsics] rework vstr_scatter_shifted_offset

Implement vstr?q_scatter_shifted_offset intrinsics using the MVE
builtins framework.

We use the same approach as the previous patch, and we now have four
sets of patterns:
- vector scatter stores with shifted offset (non-truncating)
- predicated vector scatter stores with shifted offset (non-truncating)
- truncating vector scatter stores with shifted offset
- predicated truncating vector scatter stores with shifted offset

Note that the truncating patterns do not use an iterator since there
is only one such variant: V4SI to V4HI.

We need to introduce new iterators:
- MVE_VLD_ST_scatter_shifted, same as MVE_VLD_ST_scatter without V16QI
- MVE_scatter_shift to map the mode to the shift amount

gcc/ChangeLog:

	* config/arm/arm-builtins.cc (arm_strss_qualifiers)
	(arm_strsu_qualifiers, arm_strsu_p_qualifiers)
	(arm_strss_p_qualifiers): Delete.
	* config/arm/arm-mve-builtins-base.cc (class vstrq_scatter_impl):
	Add support for shifted version.
	(vstrdq_scatter_shifted, vstrhq_scatter_shifted)
	(vstrwq_scatter_shifted): New.
	* config/arm/arm-mve-builtins-base.def (vstrhq_scatter_shifted)
	(vstrwq_scatter_shifted, vstrdq_scatter_shifted): New.
	* config/arm/arm-mve-builtins-base.h (vstrhq_scatter_shifted)
	(vstrwq_scatter_shifted, vstrdq_scatter_shifted): New.
	* config/arm/arm_mve.h (vstrhq_scatter_shifted_offset): Delete.
	(vstrhq_scatter_shifted_offset_p): Delete.
	(vstrdq_scatter_shifted_offset_p): Delete.
	(vstrdq_scatter_shifted_offset): Delete.
	(vstrwq_scatter_shifted_offset_p): Delete.
	(vstrwq_scatter_shifted_offset): Delete.
	(vstrhq_scatter_shifted_offset_s32): Delete.
	(vstrhq_scatter_shifted_offset_s16): Delete.
	(vstrhq_scatter_shifted_offset_u32): Delete.
	(vstrhq_scatter_shifted_offset_u16): Delete.
	(vstrhq_scatter_shifted_offset_p_s32): Delete.
	(vstrhq_scatter_shifted_offset_p_s16): Delete.
	(vstrhq_scatter_shifted_offset_p_u32): Delete.
	(vstrhq_scatter_shifted_offset_p_u16): Delete.
	(vstrdq_scatter_shifted_offset_p_s64): Delete.
	(vstrdq_scatter_shifted_offset_p_u64): Delete.
	(vstrdq_scatter_shifted_offset_s64): Delete.
	(vstrdq_scatter_shifted_offset_u64): Delete.
	(vstrhq_scatter_shifted_offset_f16): Delete.
	(vstrhq_scatter_shifted_offset_p_f16): Delete.
	(vstrwq_scatter_shifted_offset_f32): Delete.
	(vstrwq_scatter_shifted_offset_p_f32): Delete.
	(vstrwq_scatter_shifted_offset_p_s32): Delete.
	(vstrwq_scatter_shifted_offset_p_u32): Delete.
	(vstrwq_scatter_shifted_offset_s32): Delete.
	(vstrwq_scatter_shifted_offset_u32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_s32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_s16): Delete.
	(__arm_vstrhq_scatter_shifted_offset_u32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_u16): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p_s32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p_s16): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p_u32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p_u16): Delete.
	(__arm_vstrdq_scatter_shifted_offset_p_s64): Delete.
	(__arm_vstrdq_scatter_shifted_offset_p_u64): Delete.
	(__arm_vstrdq_scatter_shifted_offset_s64): Delete.
	(__arm_vstrdq_scatter_shifted_offset_u64): Delete.
	(__arm_vstrwq_scatter_shifted_offset_p_s32): Delete.
	(__arm_vstrwq_scatter_shifted_offset_p_u32): Delete.
	(__arm_vstrwq_scatter_shifted_offset_s32): Delete.
	(__arm_vstrwq_scatter_shifted_offset_u32): Delete.
	(__arm_vstrhq_scatter_shifted_offset_f16): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p_f16): Delete.
	(__arm_vstrwq_scatter_shifted_offset_f32): Delete.
	(__arm_vstrwq_scatter_shifted_offset_p_f32): Delete.
	(__arm_vstrhq_scatter_shifted_offset): Delete.
	(__arm_vstrhq_scatter_shifted_offset_p): Delete.
	(__arm_vstrdq_scatter_shifted_offset_p): Delete.
	(__arm_vstrdq_scatter_shifted_offset): Delete.
	(__arm_vstrwq_scatter_shifted_offset_p): Delete.
	(__arm_vstrwq_scatter_shifted_offset): Delete.
	* config/arm/arm_mve_builtins.def
	(vstrhq_scatter_shifted_offset_p_u)
	(vstrhq_scatter_shifted_offset_u)
	(vstrhq_scatter_shifted_offset_p_s)
	(vstrhq_scatter_shifted_offset_s, vstrdq_scatter_shifted_offset_s)
	(vstrhq_scatter_shifted_offset_f, vstrwq_scatter_shifted_offset_f)
	(vstrwq_scatter_shifted_offset_s)
	(vstrdq_scatter_shifted_offset_p_s)
	(vstrhq_scatter_shifted_offset_p_f)
	(vstrwq_scatter_shifted_offset_p_f)
	(vstrwq_scatter_shifted_offset_p_s)
	(vstrdq_scatter_shifted_offset_u, vstrwq_scatter_shifted_offset_u)
	(vstrdq_scatter_shifted_offset_p_u)
	(vstrwq_scatter_shifted_offset_p_u): Delete.
	* config/arm/iterators.md (MVE_VLD_ST_scatter_shifted): New.
	(MVE_scatter_shift): New.
	(supf): Remove VSTRHQSSO_S, VSTRHQSSO_U, VSTRDQSSO_S, VSTRDQSSO_U,
	VSTRWQSSO_U, VSTRWQSSO_S.
	(VSTRHSSOQ, VSTRDSSOQ, VSTRWSSOQ): Delete.
	* config/arm/mve.md (mve_vstrhq_scatter_shifted_offset_p_<supf><mode>): Delete.
	(mve_vstrhq_scatter_shifted_offset_p_<supf><mode>_insn): Delete.
	(mve_vstrhq_scatter_shifted_offset_<supf><mode>): Delete.
	(mve_vstrhq_scatter_shifted_offset_<supf><mode>_insn): Delete.
	(mve_vstrdq_scatter_shifted_offset_p_<supf>v2di): Delete.
	(mve_vstrdq_scatter_shifted_offset_p_<supf>v2di_insn): Delete.
	(mve_vstrdq_scatter_shifted_offset_<supf>v2di): Delete.
	(mve_vstrdq_scatter_shifted_offset_<supf>v2di_insn): Delete.
	(mve_vstrhq_scatter_shifted_offset_fv8hf): Delete.
	(mve_vstrhq_scatter_shifted_offset_fv8hf_insn): Delete.
	(mve_vstrhq_scatter_shifted_offset_p_fv8hf): Delete.
	(mve_vstrhq_scatter_shifted_offset_p_fv8hf_insn): Delete.
	(mve_vstrwq_scatter_shifted_offset_fv4sf): Delete.
	(mve_vstrwq_scatter_shifted_offset_fv4sf_insn): Delete.
	(mve_vstrwq_scatter_shifted_offset_p_fv4sf): Delete.
	(mve_vstrwq_scatter_shifted_offset_p_fv4sf_insn): Delete.
	(mve_vstrwq_scatter_shifted_offset_p_<supf>v4si): Delete.
	(mve_vstrwq_scatter_shifted_offset_p_<supf>v4si_insn): Delete.
	(mve_vstrwq_scatter_shifted_offset_<supf>v4si): Delete.
	(mve_vstrwq_scatter_shifted_offset_<supf>v4si_insn): Delete.
	(@mve_vstrq_scatter_shifted_offset_<mode>): New.
	(@mve_vstrq_scatter_shifted_offset_p_<mode>): New.
	(mve_vstrq_truncate_scatter_shifted_offset_v4si): New.
	(mve_vstrq_truncate_scatter_shifted_offset_p_v4si): New.
	* config/arm/unspecs.md (VSTRDQSSO_S, VSTRDQSSO_U, VSTRWQSSO_S)
	(VSTRWQSSO_U, VSTRHQSSO_F, VSTRWQSSO_F, VSTRHQSSO_S, VSTRHQSSO_U):
	Delete.
	(VSTRSSOQ, VSTRSSOQ_P, VSTRSSOQ_TRUNC, VSTRSSOQ_TRUNC_P): New.