i386: Enable AVX/AVX512 features only if supported by OSXSAVE

i386: Enable AVX/AVX512 features only if supported by OSXSAVE

Enable AVX and AVX512 features only if their states are supported by
OSXSAVE.

	PR target/85100
	* config/i386/cpuinfo.c (XCR_XFEATURE_ENABLED_MASK): New.
	(XSTATE_FP): Likewise.
	(XSTATE_SSE): Likewise.
	(XSTATE_YMM): Likewise.
	(XSTATE_OPMASK): Likewise.
	(XSTATE_ZMM): Likewise.
	(XSTATE_HI_ZMM): Likewise.
	(XCR_AVX_ENABLED_MASK): Likewise.
	(XCR_AVX512F_ENABLED_MASK): Likewise.
	(get_available_features): Enable AVX and AVX512 features only
	if their states are supported by OSXSAVE.

From-SVN: r258954