[media] pwc: Fix comment wrt lock ordering

With all the changes to handle the locking in the v4l2-core rather then at
the driver level, the order in which the 2 pwc locks need to be taken has
changed, update the comment in the header file to correctly reflect this.

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

drivers/media/usb/pwc/pwc.h

@@ -226,7 +226,7 @@ struct pwc_device
 	struct list_head queued_bufs;
 	spinlock_t queued_bufs_lock; /* Protects queued_bufs */
 
-	/* Note if taking both locks v4l2_lock must always be locked first! */
+	/* If taking both locks vb_queue_lock must always be locked first! */
 	struct mutex v4l2_lock;      /* Protects everything else */
 	struct mutex vb_queue_lock;  /* Protects vb_queue and capt_file */