This patch uses xsaves/xrstors/xsavec instead of xsaveopt/xrstor
to perform the xsave_area switching so that xen itself
can benefit from them when available.
For xsaves/xrstors/xsavec only use compact format. Add format conversion
support when perform guest os migration. Also, pv guest will not support
xsaves/xrstors.
Signed-off-by: Shuai Ruan <shuai.ruan@linux.intel.com>
[dropped redundant uses of XRSTOR_FIXUP and fix formatting] Signed-off-by: Jan Beulich <jbeulich@suse.com>