The waitqueues are already initialised during ring initialisation so
kill the redundant and duplicated code to do so in each generations IRQ
installer.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>