This reverts commit ae59b8ba41.
The commit ae59b8ba41 was added to modify the GenSmmPageTable()
to map SMRAM in 4K page granularity. It was to urgently fix a
smm hang issue by avoiding page split in paging structures that
covers SMRAM range when SMI happens. But finally the smm hang
issue was root caused and fixed by commit 839bd17973.
Meanwhile a smm page table creation related issue was introduced
by commit ae59b8ba41:
In the function GenSmmPageTable(), the paging level for the range
outside SMRAM is depend on the Input parameter PagingMode. However,
the paging level for SMRAM range is depend on m5LevelPagingNeeded.
If the two paging levels are different, then the smm page table is
created incorrectly.
So let's revert the commit "UefiCpuPkg/PiSmmCpuDxeSmm:Map SMRAM
in 4K page granularity"
Signed-off-by: Dun Tan <dun.tan@intel.com>