net: dsa: mv88e6xxx: Fix serdes irq setup going recursive

Duec to a typo, mv88e6390_serdes_irq_setup() calls itself, rather than
mv88e6390x_serdes_irq_setup(). It then blows the stack, and shortly
after the machine blows up.

Fixes: 2defda1 ("net: dsa: mv88e6xxx: Add support for SERDES on ports 2-8 for 6390X")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/serdes.c

@@ -664,7 +664,7 @@ int mv88e6390_serdes_irq_setup(struct mv88e6xxx_chip *chip, int port)
 	if (port < 9)
 		return 0;
 
-	return mv88e6390_serdes_irq_setup(chip, port);
+	return mv88e6390x_serdes_irq_setup(chip, port);
 }
 
 void mv88e6390x_serdes_irq_free(struct mv88e6xxx_chip *chip, int port)