NMI is used to notify LAPIC-PT RTVM, to kick its CPU into hypervisor.
But NMI could be used by system devices, like PMU (Performance Monitor
Unit). So use INIT signal as the partition CPU notification function, to
replace injecting NMI.
Also remove unused NMI as notification related code.
Tracked-On: #6966
Acked-by: Anthony Xu <anthony.xu@intel.com>
Signed-off-by: Minggui Cao <minggui.cao@intel.com>