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.