media: atomisp: add missing wait_prepare/finish ops

Without these ops the v4l2-compliance blocking wait test will fail.
These ops are required to ensure that when VIDIOC_DQBUF has to
wait for buffers to arrive, the queue lock is correctly released
and retaken. Otherwise the wait for a buffer would block all other
queue ioctls.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://lore.kernel.org/r/9f401f3732dd728e3d2ca508002c97b80a2eae30.1725265884.git.hverkuil-cisco@xs4all.nl


Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>