target: [PR103750] Also handle avx512 kmask & immediate 15 or 3 when VF is 4/2.

target: [PR103750] Also handle avx512 kmask & immediate 15 or 3 when VF is 4/2.

Since the upper bits are already cleared by the comparison
instructions.

gcc/ChangeLog:
	PR target/103750
	* config/i386/sse.md (*<avx512>_cmp<mode>3_and15): New define_insn.
	(*<avx512>_ucmp<mode>3_and15): Ditto.
	(*<avx512>_cmp<mode>3_and3): Ditto.
	(*avx512vl_ucmpv2di3_and3): Ditto.
	(*<avx512>_cmp<V48H_AVX512VL:mode>3_zero_extend<SWI248x:mode>):
	Change operands[3] predicate to <cmp_imm_predicate>.
	(*<avx512>_cmp<V48H_AVX512VL:mode>3_zero_extend<SWI248x:mode>_2):
	Ditto.
	(*<avx512>_cmp<mode>3): Add GET_MODE_NUNITS (<MODE>mode) >= 8
	to the condition.
	(*<avx512>_ucmp<mode>3): Ditto.
	(V48_AVX512VL_4): New mode iterator.
	(VI48_AVX512VL_4): Ditto.
	(V8_AVX512VL_2): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/avx512vl-pr103750-1.c: New test.
	* gcc.target/i386/avx512f-pr96891-3.c: Adjust testcase.
	* gcc.target/i386/avx512f-vpcmpgtuq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpeqq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpequq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpgeq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpgeuq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpgtq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpgtuq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpleq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpleuq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpltq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpltuq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpneqq-1.c: Ditto.
	* gcc.target/i386/avx512vl-vpcmpnequq-1.c: Ditto.