re PR target/77476 ([AVX-512] illegal kmovb instruction on KNL)

re PR target/77476 ([AVX-512] illegal kmovb instruction on KNL)

	PR target/77476
	* config/i386/i386.md (isa): Add x64_avx512bw.
	(*zero_extendsidi2): For alternative 11 use x64_avx512bw isa.
	(kmov_isa): New mode attr.
	(zero_extend<mode>di2): Use <kmov_isa> isa for the last alternative.
	(*zero_extend<mode>si2): Likewise.
	(*zero_extendqihi2): Use avx512dq isa for the last alternative.

	* gcc.target/i386/avx512f-pr77476.c: New test.
	* gcc.target/i386/avx512bw-pr77476.c: New test.
	* gcc.target/i386/avx512dq-pr77476.c: New test.

From-SVN: r240000