net: dsa: mv88e6xxx: Fix mv88e6xxx_g1_irq_free() interrupt count

mv88e6xxx_g1_irq_setup() sets up chip->g1_irq.nirqs interrupt mappings,
so free the same amount. This will be 8 or 9 in practice, less than 16.

Fixes: dc30c35be7 ("net: dsa: mv88e6xxx: Implement interrupt support.")
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -421,7 +421,7 @@ static void mv88e6xxx_g1_irq_free(struct mv88e6xxx_chip *chip)
 
 	free_irq(chip->irq, chip);
 
-	for (irq = 0; irq < 16; irq++) {
+	for (irq = 0; irq < chip->g1_irq.nirqs; irq++) {
 		virq = irq_find_mapping(chip->g1_irq.domain, irq);
 		irq_dispose_mapping(virq);
 	}