UefiCpuPkg/MpInitLib: Move save/restore interrupt to SwitchBSPWorker()

UefiCpuPkg/MpInitLib: Move save/restore interrupt to SwitchBSPWorker()

During switching BSP phase, we need to disable CPU interruput to prevent stack
crashed by Timer interrupt handle. But when we enabled source debugging feature,
debug timer interrupt handler (existing on both PEI and DXE) also could crash
the stack used during switching BSP. So,we need to move save/restore interrupt
to SwitchBSPWorker().

Cc: Feng Tian <feng.tian@intel.com>
Cc: Kinney Michael D <michael.d.kinney@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@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>