net: dsa: microchip: Fix KSZ9477 HSR port setup issue

ksz9477_hsr_join() is called once to setup the HSR port membership, but
the port can be enabled later, or disabled and enabled back and the port
membership is not set correctly inside ksz_update_port_member().  The
added code always use the correct HSR port membership for HSR port that
is enabled.

Fixes: 2d61298 ("net: dsa: microchip: Enable HSR offloading for KSZ9477")
Reported-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Tristram Ha <tristram.ha@microchip.com>
Reviewed-by: Łukasz Majewski <lukma@nabladev.com>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Link: https://patch.msgid.link/20250819010457.563286-1-Tristram.Ha@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: triha2work

drivers/net/dsa/microchip/ksz_common.c

@@ -2457,6 +2457,12 @@ static void ksz_update_port_member(struct ksz_device *dev, int port)
 		dev->dev_ops->cfg_port_member(dev, i, val | cpu_port);
 	}
 
+	/* HSR ports are setup once so need to use the assigned membership
+	 * when the port is enabled.
+	 */
+	if (!port_member && p->stp_state == BR_STATE_FORWARDING &&
+	    (dev->hsr_ports & BIT(port)))
+		port_member = dev->hsr_ports;
 	dev->dev_ops->cfg_port_member(dev, port, port_member | cpu_port);
 }