UefiCpuPkg/CpuMpPei: Set X2APIC flag if one x2APIC ID larger than 254

UefiCpuPkg/CpuMpPei: Set X2APIC flag if one x2APIC ID larger than 254

If there are any logical processor reporting an APIC ID of 255 or greater, set
X2ApicEnable flag.

GetInitialApicId() will return x2APIC ID if CPUID leaf B supported.

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: Michael Kinney <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18933 6f19259b-4bc3-4df7-8a09-765794883524