AVX512FP16: Add testcase for vrcpph/vrcpsh/vscalefph/vscalefsh.
gcc/testsuite/ChangeLog:
* gcc.target/i386/avx512fp16-vrcpph-1a.c: New test.
* gcc.target/i386/avx512fp16-vrcpph-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vrcpsh-1a.c: Ditto.
* gcc.target/i386/avx512fp16-vrcpsh-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vscalefph-1a.c: Ditto.
* gcc.target/i386/avx512fp16-vscalefph-1b.c: Ditto.
* gcc.target/i386/avx512fp16-vscalefsh-1a.c: Ditto.
* gcc.target/i386/avx512fp16-vscalefsh-1b.c: Ditto.
* gcc.target/i386/avx512fp16vl-vrcpph-1a.c: Ditto.
* gcc.target/i386/avx512fp16vl-vrcpph-1b.c: Ditto.
* gcc.target/i386/avx512fp16vl-vscalefph-1a.c: Ditto.
* gcc.target/i386/avx512fp16vl-vscalefph-1b.c: Ditto.