[media] V4L: soc-camera: add helper functions for videobuf queue handling

Add two helper inline functions to retrieve soc-camera device context
from videobuf and videobuf2 queue pointers.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

include/media/soc_camera.h

@@ -306,6 +306,16 @@ static inline struct video_device *soc_camera_i2c_to_vdev(struct i2c_client *cli
 	return icd->vdev;
 }
 
+static inline struct soc_camera_device *soc_camera_from_vb2q(struct vb2_queue *vq)
+{
+	return container_of(vq, struct soc_camera_device, vb2_vidq);
+}
+
+static inline struct soc_camera_device *soc_camera_from_vbq(struct videobuf_queue *vq)
+{
+	return container_of(vq, struct soc_camera_device, vb_vidq);
+}
+
 void soc_camera_lock(struct vb2_queue *vq);
 void soc_camera_unlock(struct vb2_queue *vq);