drm/ttm: Export symbols needed for the vmwgfx driver.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index e8cd6d2..7a39ab9 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -545,6 +545,15 @@
 extern int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem);
 
 /**
+ * ttm_tt_populate:
+ *
+ * @ttm: The struct ttm_tt to contain the backing pages.
+ *
+ * Add backing pages to all of @ttm
+ */
+extern int ttm_tt_populate(struct ttm_tt *ttm);
+
+/**
  * ttm_ttm_destroy:
  *
  * @ttm: The struct ttm_tt.