net: lan966x: Make sure to release ptp interrupt

When the lan966x driver is removed make sure to remove also the ptp_irq
IRQ.

Fixes: e85a96e4 ("net: lan966x: Add support for ptp interrupts")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Link: https://lore.kernel.org/r/20220413195716.3796467-1-horatiu.vultur@microchip.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/microchip/lan966x/lan966x_main.c

@@ -671,6 +671,9 @@ static void lan966x_cleanup_ports(struct lan966x *lan966x)
 		disable_irq(lan966x->ana_irq);
 		lan966x->ana_irq = -ENXIO;
 	}
+
+	if (lan966x->ptp_irq)
+		devm_free_irq(lan966x->dev, lan966x->ptp_irq, lan966x);
 }
 
 static int lan966x_probe_port(struct lan966x *lan966x, u32 p,