Emulate SYSENTER in Compatibility Mode for all vCPUs models that are
compatible with Intel's architecture, as the behavior if SYSENTER is
architecturally defined in Intel's SDM, i.e. should be followed by any
CPU that implements Intel's architecture.

Link: https://lore.kernel.org/r/20240405235603.1173076-9-seanjc@google.comSigned-off-by: Sean Christopherson <seanjc@google.com>