[netdrvr] irq handler minor cleanups in several drivers

* use irq_handler_t where appropriate

* no need to use 'irq' function arg, its already stored in a data struct

* rename irq handler 'irq' argument to 'dummy', where the function
  has been analyzed and proven not to use its first argument.

* remove always-false "dev_id == NULL" test from irq handlers

* remove pointless casts from void*

* declance: irq argument is not const

* add KERN_xxx printk prefix

* fix minor whitespace weirdness

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/ibmlana.c b/drivers/net/ibmlana.c
index 91d83ac..65626d6 100644
--- a/drivers/net/ibmlana.c
+++ b/drivers/net/ibmlana.c
@@ -704,9 +704,9 @@
 
 /* general interrupt entry */
 
-static irqreturn_t irq_handler(int irq, void *device)
+static irqreturn_t irq_handler(int dummy, void *device)
 {
-	struct net_device *dev = (struct net_device *) device;
+	struct net_device *dev = device;
 	u16 ival;
 
 	/* in case we're not meant... */