media: atomisp: Drop atomisp_pipe_check() from atomisp_link_setup()

The media-controller core (__media_entity_setup_link()) already checks
that the pads of the link are not streaming before calling the setup_link()
pad-op so calling atomisp_pipe_check() is not necessary;

and taking isp->mutex inside the setup_link() pad-op leads to a possible
ABBA deadlock vs the media-device graph_mutex which in the case of
the setup_link() pad-op is taken before calling the op, while in other
scenarios the graph_mutex is taken after the isp->mutex.

Reviewed-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Hans de Goede <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/staging/media/atomisp/pci/atomisp_subdev.c

···
 					      entity);
 	struct atomisp_sub_device *asd = v4l2_get_subdevdata(sd);
 	struct atomisp_device *isp = asd->isp;
-	int i, ret;
+	int i;
 
 	/* ISP's source is immutable */
 	if (local != &asd->pads[ATOMISP_SUBDEV_PAD_SINK]) {
···
 		v4l2_err(sd, "Error no sensor for selected CSI receiver\n");
 		return -EINVAL;
 	}
-
-	mutex_lock(&isp->mutex);
-	ret = atomisp_pipe_check(&asd->video_out, true);
-	mutex_unlock(&isp->mutex);
-	if (ret)
-		return ret;
 
 	/* Turn off the sensor on link disable */
 	if (!(flags & MEDIA_LNK_FL_ENABLED)) {