Remove static and inline attributes to the API is_x2apic_enabled
and declare a prototype in vlapic.h. Also fix the check performed on guest
APICBASE_MSR value to query vLAPIC mode.
Tracked-On: #3253
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>