Staging: VME: Fix ca91cx42 VME interrupt generation.

The wait_event_interruptible call requires a condition as second argument that
needs to be true sometimes, which is obviously not the case with '0'. The new
logic is inspired from the tsi148 driver and takes into account Universe II chip
specifics.

Signed-off-by: Vincent Bossier <vincent.bossier@gmail.com>
Acked-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>