Integrate r1.339 of vmm.c which I missed during the previous MI/MD split

Integrate r1.339 of vmm.c which I missed during the previous MI/MD split

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revision 1.339
date: 2023/04/22 18:27:28;  author: guenther;  state: Exp;  lines: +3 -3;  commitid: ajtkYPSAhtJdB488;
Rename the XCR0_* #defines to XFEATURE_* and add the new supervisor-state
features: while all are appropriate for xsaves/xrstors, the
supervisor-state features aren't for xcr0 but rather for the new XSS_MSR,
making the current names kinda confusing.

Add #defines for masking bits for xcr0 vs XSS.

Add and report the new XSAVE_XFD xsave subfeature bit.
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