Minor update to logic to prevent writing a the read-only MSI Capability bit with 0 when HPET supports MSIs
Signed-off-by: mdkinney
Reviewed-by: li-elvin
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12272 6f19259b-4bc3-4df7-8a09-765794883524