net: dsa: Fix type was not set for devlink port

[ Upstream commit fb6ec87 ]

If PHY is not available on DSA port (described at devicetree but absent or
failed to detect) then kernel prints warning after 3700 secs:

[ 3707.948771] ------------[ cut here ]------------
[ 3707.948784] Type was not set for devlink port.
[ 3707.948894] WARNING: CPU: 1 PID: 17 at net/core/devlink.c:8097 0xc083f9d8

We should unregister the devlink port as a user port and
re-register it as an unused port before executing "continue" in case of
dsa_port_setup error.

Fixes: 86f8b1c ("net: dsa: Do not make user port errors fatal")
Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

net/dsa/dsa2.c

@@ -533,8 +533,14 @@ static int dsa_tree_setup_switches(struct dsa_switch_tree *dst)
 
 	list_for_each_entry(dp, &dst->ports, list) {
 		err = dsa_port_setup(dp);
-		if (err)
+		if (err) {
+			dsa_port_devlink_teardown(dp);
+			dp->type = DSA_PORT_TYPE_UNUSED;
+			err = dsa_port_devlink_setup(dp);
+			if (err)
+				goto teardown;
 			continue;
+		}
 	}
 
 	return 0;