x86: quirk for reboot stalls on a Dell Optiplex 330

Dell Optiplex 330 appears to hang on reboot. This is resolved by adding
a quirk to set bios reboot.

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: Steve Conklin <steve.conklin@canonical.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>