The memory will be set to background color after success allocate
the data, so not need to call AllocateZeroPool.
Related bugz: https://bugzilla.tianocore.org/show_bug.cgi?id=223
Cc: Dandan Bi <dandan.bi@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>