AVX512FP16: Adjust builtin name for FP16 builtins to match AVX512F style

For AVX512FP16 builtins, they all contain format like vaddph_v8hf,
while AVX512F builtins use addps128 which succeeded SSE/AVX style.
Adjust AVX512FP16 builtins to match such format.

gcc/ChangeLog:

	* config/i386/avx512fp16intrin.h: Adjust all builtin calls.
	* config/i386/avx512fp16vlintrin.h: Likewise.
	* config/i386/i386-builtin.def: Adjust builtin name and
	enumeration to match AVX512F style.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/avx-1.c: Adjust builtin macros.
	* gcc.target/i386/sse-13.c: Likewise.
	* gcc.target/i386/sse-23.c: Likewise.