3c503: fix broken IRQ autoprobing

Fix broken IRQ autoprobing in 3c503 driver:
 - improper IRQ freeing (does not free IRQs causes WARN)
 - missing break when an working IRQ is found

The driver works with this patch.
Signed-off-by: NOndrej Zary <linux@rainbow-software.org>
Reviewed-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NDavid S. Miller <davem@conan.davemloft.net>

drivers/net/3c503.c

@@ -412,7 +412,7 @@ el2_open(struct net_device *dev)
 		outb_p(0x04 << ((*irqp == 9) ? 2 : *irqp), E33G_IDCFR);
 		outb_p(0x00, E33G_IDCFR);
 		msleep(1);
-		free_irq(*irqp, el2_probe_interrupt);
+		free_irq(*irqp, &seen);
 		if (!seen)
 			continue;
 
@@ -422,6 +422,7 @@ el2_open(struct net_device *dev)
 			continue;
 		if (retval < 0)
 			goto err_disable;
+		break;
 	} while (*++irqp);
 
 	if (*irqp == 0) {