staging: media: ipu3: remove redundant assignment to pointer css_pipe

Pointer css_pipe is being assigned a value that is never read afterwards.
The assignment is redundant and can be removed.

Cleans up clang scan build warning:
drivers/staging/media/ipu3/ipu3-css.c:2058:3: warning: Value stored
to 'css_pipe' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/staging/media/ipu3/ipu3-css.c

@@ -2055,7 +2055,6 @@ struct imgu_css_buffer *imgu_css_buf_dequeue(struct imgu_css *css)
 			return ERR_PTR(-EIO);
 		}
 
-		css_pipe = &css->pipes[pipe];
 		dev_dbg(css->dev, "event: pipeline done 0x%8x for pipe %d\n",
 			event, pipe);
 		break;