AVX512FP16: Add testcase for vmaxph/vmaxsh/vminph/vminsh.
gcc/testsuite/ChangeLog:
* gcc.target/i386/avx512fp16-vmaxph-1a.c: New test.
* gcc.target/i386/avx512fp16-vmaxph-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vmaxsh-1.c: Ditto.
* gcc.target/i386/avx512fp16-vmaxsh-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vminph-1a.c: Ditto.
* gcc.target/i386/avx512fp16-vminph-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vminsh-1.c: Ditto.
* gcc.target/i386/avx512fp16-vminsh-1b.c: Ditto.
* gcc.target/i386/avx512fp16vl-vmaxph-1a.c: Ditto.
* gcc.target/i386/avx512fp16vl-vmaxph-1b.c: Ditto.
* gcc.target/i386/avx512fp16vl-vminph-1a.c: Ditto.
* gcc.target/i386/avx512fp16vl-vminph-1b.c: Ditto.