arm: [MVE intrinsics] Remove unused builtins qualifiers

arm: [MVE intrinsics] Remove unused builtins qualifiers

After the re-implementation of MVE vld/vst intrinsics, a few builtins
qualifiers became useless.

This patch removes them to restore bootstrap (otherwise the build
fails because of 'defined but not used' errors.

gcc/ChangeLog:

	* config/arm/arm-builtins.cc (STRS_QUALIFIERS): Delete.
	(STRU_QUALIFIERS): Delete.
	(STRS_P_QUALIFIERS): Delete.
	(STRU_P_QUALIFIERS): Delete.
	(LDRS_QUALIFIERS): Delete.
	(LDRU_QUALIFIERS): Delete.
	(LDRS_Z_QUALIFIERS): Delete.
	(LDRU_Z_QUALIFIERS): Delete.