Added support for performance counter that counts up or down Signed-off-by: Olivier Martin <olivier.martin@arm.com> git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13747 6f19259b-4bc3-4df7-8a09-765794883524
Added support for performance counter that counts up or down Signed-off-by: Olivier Martin <olivier.martin@arm.com> git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13747 6f19259b-4bc3-4df7-8a09-765794883524