drm/radeon: Calling object_unrefer() when creating fb failure

When kzalloc() failed in radeon_user_framebuffer_create(), need to
call object_unreference() to match the object_reference().

Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Signed-off-by: xueminsu <xuemin.su@intel.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index ff3def7..05c96fa 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -1115,8 +1115,10 @@
 	}
 
 	radeon_fb = kzalloc(sizeof(*radeon_fb), GFP_KERNEL);
-	if (radeon_fb == NULL)
+	if (radeon_fb == NULL) {
+		drm_gem_object_unreference_unlocked(obj);
 		return ERR_PTR(-ENOMEM);
+	}
 
 	ret = radeon_framebuffer_init(dev, radeon_fb, mode_cmd, obj);
 	if (ret) {