x86: Disable SSE in ISA2 for -mgeneral-regs-only

Replace OPTION_MASK_ISA2_AVX512F_UNSET with OPTION_MASK_ISA2_SSE_UNSET
in OPTION_MASK_ISA2_GENERAL_REGS_ONLY_UNSET to disable SSE, AVX and
AVX512 ISAs.

gcc/

	PR target/105000
	* common/config/i386/i386-common.cc
	(OPTION_MASK_ISA2_GENERAL_REGS_ONLY_UNSET): Replace
	OPTION_MASK_ISA2_AVX512F_UNSET with OPTION_MASK_ISA2_SSE_UNSET.

gcc/testsuite/

	PR target/105000
	* gcc.target/i386/pr105000-1.c: New test.
	* gcc.target/i386/pr105000-2.c: Likewise.
	* gcc.target/i386/pr105000-3.c: Likewise.
	* gcc.target/i386/pr105000-4.c: Likewise.