media: atmel-isi: Fix crash due to missing subdev in state

As a result of converting to the stream-aware state functions, commit
bc0e8d91feec ("media: v4l: subdev: Switch to stream-aware state
functions") caused the sd pointer of the state passed to the
v4l2_subdev_state_get_crop() function to be dereferenced. It however
missed that the atmel-isi driver creates the v4l2_subdev_state instance
on the stack (which it shouldn't do, but that's a separate problem),
without initializing the sd field. This results in a null pointer
dereference.

Fix it by initializing the sd field.

Fixes: bc0e8d91feec ("media: v4l: subdev: Switch to stream-aware state functions")
Signed-off-by: Laurent Pinchart <[e-mail]>
Signed-off-by: Sakari Ailus <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>

drivers/media/platform/atmel/atmel-isi.c

···
 	struct v4l2_pix_format *pixfmt = &f->fmt.pix;
 	struct v4l2_subdev_pad_config pad_cfg = {};
 	struct v4l2_subdev_state pad_state = {
+		.sd = isi->entity.subdev,
 		.pads = &pad_cfg,
 	};
 	struct v4l2_subdev_format format = {