[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/wireless/airo.c b/drivers/net/wireless/airo.c
index e3eca6d..d8948bf 100644
--- a/drivers/net/wireless/airo.c
+++ b/drivers/net/wireless/airo.c
@@ -3177,8 +3177,9 @@
 	return 0;
 }
 
-static irqreturn_t airo_interrupt ( int irq, void* dev_id) {
-	struct net_device *dev = (struct net_device *)dev_id;
+static irqreturn_t airo_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
 	u16 status;
 	u16 fid;
 	struct airo_info *apriv = dev->priv;