I created the correct IDT and GDT which was wrongly created before.
Comments were updated to reflect the actual meaning of the code and IDT alignment was set to 8 byte.
Some unnecessary alginments were removed.
DUET x64 MSFT and GCC both can boot to front page now.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9845 6f19259b-4bc3-4df7-8a09-765794883524