2. Modified SwitchStack definition update to MWG 0.60e.
3. Added BaseLib/Ipf/InternalSwitchStack.c and removed BaseLib/Ipf/Non-existing.c
4. Updated any references of AsmSwitchStackAndBackingStore to SwichStack on IPF.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2499 6f19259b-4bc3-4df7-8a09-765794883524