MdePkg/BaseUefiDecompressLib: Improve performance of boundary validation

MdePkg/BaseUefiDecompressLib: Improve performance of boundary validation

The boundary validation checking in MakeTable() performs on
every loop iteration. This could be improved by checking
just once before the loop.
https://bugzilla.tianocore.org/show_bug.cgi?id=1329

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>