ttm: export functions to allow qxl do its own iomapping

qxl wants to use io mapping like i915 gem does, for now
just export the symbols so the driver can implement atomic
page maps using io mapping.

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 0fbd046..9c8dca7 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -902,6 +902,10 @@
  * ttm_bo_util.c
  */
 
+int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
+		       struct ttm_mem_reg *mem);
+void ttm_mem_io_free(struct ttm_bo_device *bdev,
+		     struct ttm_mem_reg *mem);
 /**
  * ttm_bo_move_ttm
  *