https://bugzilla.tianocore.org/show_bug.cgi?id=624 reports
memory protection crash in PiSmmCpuDxeSmm, Ia32 build with
RAM above 4GB (of which 2GB are placed in 64-bit address).
It is because UEFI builds identity mapping page tables,
>4G address is not supported at Ia32 build.
This patch is to get the PhysicalAddressBits that is used
to build in PageTbl.c(Ia32/X64), and use it to check whether
the address is supported or not in ConvertMemoryPageAttributes().