drm: remove redundant minor->device field

Whenever we access minor->device, we are in a minor->kdev->...->fops
callback so the minor->kdev pointer *must* be valid. Thus, simply use
minor->kdev->devt instead of minor->device and remove the redundant field.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_drv.c

@@ -344,7 +344,7 @@ long drm_ioctl(struct file *filp,
 
 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
 		  task_pid_nr(current),
-		  (long)old_encode_dev(file_priv->minor->device),
+		  (long)old_encode_dev(file_priv->minor->kdev->devt),
 		  file_priv->authenticated, ioctl->name);
 
 	/* Do not trust userspace, use our own definition */
@@ -402,7 +402,7 @@ long drm_ioctl(struct file *filp,
 	if (!ioctl)
 		DRM_DEBUG("invalid ioctl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
 			  task_pid_nr(current),
-			  (long)old_encode_dev(file_priv->minor->device),
+			  (long)old_encode_dev(file_priv->minor->kdev->devt),
 			  file_priv->authenticated, cmd, nr);
 
 	if (kdata != stack_kdata)

drivers/gpu/drm/drm_fops.c

@@ -471,7 +471,7 @@ int drm_release(struct inode *inode, struct file *filp)
 
 	DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 		  task_pid_nr(current),
-		  (long)old_encode_dev(file_priv->minor->device),
+		  (long)old_encode_dev(file_priv->minor->kdev->devt),
 		  dev->open_count);
 
 	/* Release any auth tokens that might point to this file_priv,

drivers/gpu/drm/drm_stub.c

@@ -318,7 +318,6 @@ static int drm_minor_register(struct drm_device *dev, unsigned int type)
 	if (minor_id < 0)
 		return minor_id;
 
-	new_minor->device = MKDEV(DRM_MAJOR, minor_id);
 	new_minor->index = minor_id;
 
 	idr_replace(&drm_minors_idr, new_minor, minor_id);

include/drm/drmP.h

@@ -1043,7 +1043,6 @@ struct drm_info_node {
 struct drm_minor {
 	int index;			/**< Minor device number */
 	int type;                       /**< Control or render */
-	dev_t device;			/**< Device number for mknod */
 	struct device *kdev;		/**< Linux device */
 	struct drm_device *dev;