drm/vmwgfx: Fix uninitialized return in vmw_cotable_unbind()

Function vmw_cotable_unbind() uses the uninitialized variable ret as
return value. Make the result deterministic and directly return as
the variable is unused anyway. Detected by Coverity CID 1324256.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>

drivers/gpu/drm/vmwgfx/vmwgfx_cotable.c

@@ -311,7 +311,6 @@ static int vmw_cotable_unbind(struct vmw_resource *res,
 	struct vmw_private *dev_priv = res->dev_priv;
 	struct ttm_buffer_object *bo = val_buf->bo;
 	struct vmw_fence_obj *fence;
-	int ret;
 
 	if (list_empty(&res->mob_head))
 		return 0;
@@ -328,7 +327,7 @@ static int vmw_cotable_unbind(struct vmw_resource *res,
 	if (likely(fence != NULL))
 		vmw_fence_obj_unreference(&fence);
 
-	return ret;
+	return 0;
 }
 
 /**