Clean up code.

Contributed-under: TianoCore Contribution Agreement 1.0

Signed off by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed by: Eric Dong <eric.dong@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15766 6f19259b-4bc3-4df7-8a09-765794883524