[Libvir] PATCH: Fix crash parsing input devices for QEMU

There is an edge case in parsing of input devices where if you have a PS2 mouse defined, before a USB tablet, it could generate a null pointer deference & thus crash. Normally you'd only have one pointer defined, but one might add a USB tablet for getting a improved mouse experience. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|