AVX512FP16: Enable vec_cmpmn/vcondmn expanders for HF modes.

AVX512FP16: Enable vec_cmpmn/vcondmn expanders for HF modes.

gcc/ChangeLog:

	* config/i386/i386-expand.c (ix86_use_mask_cmp_p): Enable
	HFmode mask_cmp.
	* config/i386/sse.md (sseintvecmodelower): Add HF vector modes.
	(<avx512>_store<mode>_mask): Extend to support HF vector modes.
	(vec_cmp<mode><avx512fmaskmodelower>): Likewise.
	(vcond_mask_<mode><avx512fmaskmodelower>): Likewise.
	(vcond<mode><mode>): New expander.
	(vcond<mode><sseintvecmodelower>): Likewise.
	(vcond<sseintvecmodelower><mode>): Likewise.
	(vcondu<mode><sseintvecmodelower>): Likewise.

gcc/testsuite/ChangeLog:

	* g++.target/i386/avx512fp16-vcondmn-vec.C: New test.
	* g++.target/i386/avx512fp16-vcondmn-minmax.C: Ditto.
	* gcc.target/i386/avx512fp16-vcondmn-loop-1.c: Ditto.
	* gcc.target/i386/avx512fp16-vcondmn-loop-2.c: Ditto.
	* gcc.target/i386/avx512fp16-vec_cmpmn.c: Ditto.