net: hns3: clean up a return in hclge_tm_bp_setup()

Smatch complains that "ret" might be uninitialized if we don't enter
the loop.  We do always enter the loop so it's a false positive, but
it's cleaner to just return a literal zero and that silences the
warning as well.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20201023112212.GA282278@mwandaSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_tm.c

@@ -1373,7 +1373,7 @@ static int hclge_tm_bp_setup(struct hclge_dev *hdev)
 			return ret;
 	}
 
-	return ret;
+	return 0;
 }
 
 int hclge_pause_setup_hw(struct hclge_dev *hdev, bool init)