AVX512FP16: Add permutation and mask blend intrinsics.
gcc/ChangeLog:
* config/i386/avx512fp16intrin.h:
(_mm512_mask_blend_ph): New intrinsic.
(_mm512_permutex2var_ph): Ditto.
(_mm512_permutexvar_ph): Ditto.
* config/i386/avx512fp16vlintrin.h:
(_mm256_mask_blend_ph): New intrinsic.
(_mm256_permutex2var_ph): Ditto.
(_mm256_permutexvar_ph): Ditto.
(_mm_mask_blend_ph): Ditto.
(_mm_permutex2var_ph): Ditto.
(_mm_permutexvar_ph): Ditto.
gcc/testsuite/ChangeLog:
* gcc.target/i386/avx512fp16-14.c: New test.