UefiCpuPkg/MpInitLib: save/restore original contents
If APs is in HLT-LOOP mode, we need AP reset vector for waking up APs. This
updating is to save/restore original contents of AP reset vector around waking
up APs always.
https://bugzilla.tianocore.org/show_bug.cgi?id=500
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>