- suppress unwanted kernel logs
- avoids passing modifier keys to the guest OS when typing in the Monitor
- fixes the bug that the mouse cursor grab is released with _any_ modifier key
  (should be only ctrl+alt)
- removes some code redundancies


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1721 c046a42c-6fe2-441c-8c8c-71466251a162