drm: use noop_llseek

The drm device drivers currently allow seeking on the
character device but never care about the actual
file position.

When we change the default llseek operation to be
no_llseek, calling llseek on a drm device would
return an error condition, which is an API change.

Explicitly setting noop_llseek lets us keep the
current API.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org

drivers/gpu/drm/i810/i810_drv.c

@@ -63,6 +63,7 @@ static struct drm_driver driver = {
 		 .mmap = drm_mmap,
 		 .poll = drm_poll,
 		 .fasync = drm_fasync,
+		 .llseek = noop_llseek,
 	},
 
 	.pci_driver = {