Delete incorrect representations of avx2 shifts.

Delete incorrect representations of avx2 shifts.

	* config/i386/i386.c (bdesc_args): Update code for
	__builtin_ia32_palignr256.  Change type of __builtin_ia32_pslldqi256,
	and __builtin_ia32_psrldqi256 to V4DI_FTYPE_V4DI_INT_CONVERT.
	(ix86_expand_args_builtin): Handle V4DI_FTYPE_V4DI_INT_CONVERT.
	* config/i386/sse.md (mode iterator V16): Add V2TI.
	(mode iterator SSESCALARMODE): Use V2TI not V4DI.
	(mode attr ssse3_avx2): Add V2TI.
	(avx2_lshrqv4di3, avx2_lshlqv4di3): Remove.

From-SVN: r179668