[PATCH][i386,AVX] Enable VNNI support [4/5]

[Koval, Julia]

Hi,
This patch enables VPDPWSSD instruction. The doc for isaset and instruction: 
https://software.intel.com/sites/default/files/managed/c5/15/architecture-instruction-set-extensions-programming-reference.pdf

Ok for trunk?

Thanks,
Julia

gcc/
        * config/i386/avx512vnniintrin.h (_mm512_dpwssd_epi32,
        _mm512_mask_dpwssd_epi32, _mm512_maskz_dpwssd_epi32): New intrinsics.
        * config/i386/avx512vnnivlintrin.h (_mm256_dpwssd_epi32,
        _mm256_mask_dpwssd_epi32, _mm256_maskz_dpwssd_epi32, _mm_dpwssd_epi32,
        _mm_mask_dpwssd_epi32, _mm_maskz_dpwssd_epi32): Ditto.

gcc/testsuite/
        * gcc.target/i386/avx512f-vnni-1.c: Add vdpwssd checks.
        * gcc.target/i386/avx512vl-vnni-1.c: Ditto.
        * gcc.target/i386/avx512f-vpdpwssd-2.c: New.
        * gcc.target/i386/avx512vl-vpdpwssd-2.c: Ditto.

0013-VPDPWSSD-instruction.patch
Description: 0013-VPDPWSSD-instruction.patch