smc91x: fix compile error when SMC_DEBUG >= 2

When SMC_DEBUG >= 2, we hit the following compilation error:

drivers/net/ethernet/smsc/smc91x.c:85:0:
drivers/net/ethernet/smsc/smc91x.c: In function ‘smc_findirq’:
drivers/net/ethernet/smsc/smc91x.c:1784:9: error: ‘dev’ undeclared (first use in this function)
  DBG(2, dev, "%s: %s\n", CARDNAME, __func__);
         ^
Fix it by passing in the appropriate netdev pointer.
Signed-off-by: NZi Shen Lim <zlim.lnx@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/smsc/smc91x.c

@@ -1781,7 +1781,7 @@ static int smc_findirq(struct smc_local *lp)
 	int timeout = 20;
 	unsigned long cookie;
 
-	DBG(2, dev, "%s: %s\n", CARDNAME, __func__);
+	DBG(2, lp->dev, "%s: %s\n", CARDNAME, __func__);
 
 	cookie = probe_irq_on();