is_lapic_pt_enabled() is called at least twice in one loop of the vCPU
thread, and it's called in vmexit_handler() frequently if LAPIC is not
pass-through. Thus the efficiency of this function has direct
impact to the system performance.
Since the LAPIC mode is not changed in run time, we don't have to
calculate it on the fly in is_lapic_pt_enabled().
BTW, removed the unused lapic_mask from struct acrn_vcpu_arch.
Tracked-On: #6289
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>