UefiCpuPkg/PiSmmCpuDxeSmm: Check ProcessorId == INVALID_APIC_ID

UefiCpuPkg/PiSmmCpuDxeSmm: Check ProcessorId == INVALID_APIC_ID

If PcdCpuHotPlugSupport is TRUE, gSmst->NumberOfCpus will be the
PcdCpuMaxLogicalProcessorNumber. If gSmst->SmmStartupThisAp() is invoked for
those un-existed processors, ASSERT() happened in ConfigSmmCodeAccessCheck().

This fix is to check if ProcessorId is valid before invoke
gSmst->SmmStartupThisAp() in ConfigSmmCodeAccessCheck() and to check if
ProcessorId is valid in InternalSmmStartupThisAp() to avoid unexpected DEBUG
error message displayed.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>