Always set WP in CR0.

Always set WP in CR0.

Always set RW+P bit for page table by default.

So that we can use write-protection for code later.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: "Kinney, Michael D" <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18960 6f19259b-4bc3-4df7-8a09-765794883524