CPUs with TAA_NO bit of IA32_ARCH_CAPABILITIES MSR set to 1 are not
vulnerable to TSX Asynchronous Abort and passing this bit to a guest
may avoid unnecessary mitigations.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>