drm: fix all sparse warning on 32-bit x86

Finally cleaned up the sparse warnings for the drm.

Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/drm_bufs.c b/drivers/char/drm/drm_bufs.c
index e3d372a..58e513a 100644
--- a/drivers/char/drm/drm_bufs.c
+++ b/drivers/char/drm/drm_bufs.c
@@ -117,9 +117,9 @@
  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
  * applicable and if supported by the kernel.
  */
-int drm_addmap_core(drm_device_t * dev, unsigned int offset,
-		    unsigned int size, drm_map_type_t type,
-		    drm_map_flags_t flags, drm_map_list_t ** maplist)
+static int drm_addmap_core(drm_device_t * dev, unsigned int offset,
+			   unsigned int size, drm_map_type_t type,
+			   drm_map_flags_t flags, drm_map_list_t ** maplist)
 {
 	drm_map_t *map;
 	drm_map_list_t *list;