drm/radeon/kms: Check if bo we got from ttm are radeon object or not

If they are not radeon object don't do anythings special for them,
this avoid rare oops than can happen in a complex use case.

[airlied: additional fixups]

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index c938bb5..e3c4940 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1016,6 +1016,7 @@
 extern void radeon_legacy_set_clock_gating(struct radeon_device *rdev, int enable);
 extern void radeon_atom_set_clock_gating(struct radeon_device *rdev, int enable);
 extern void radeon_ttm_placement_from_domain(struct radeon_bo *rbo, u32 domain);
+extern bool radeon_ttm_bo_is_radeon_bo(struct ttm_buffer_object *bo);
 
 /* r100,rv100,rs100,rv200,rs200,r200,rv250,rs300,rv280 */
 struct r100_mc_save {