IRQ: Use the new typedef for interrupt handler function pointers

Use the new typedef for interrupt handler function pointers rather than
actually spelling out the full thing each time.  This was scripted with the
following small shell script:

#!/bin/sh
egrep -nHrl -e 'irqreturn_t[ 	]*[(][*]' $* |
while read i
do
    echo $i
    perl -pi -e 's/irqreturn_t\s*[(]\s*[*]\s*([_a-zA-Z0-9]*)\s*[)]\s*[(]\s*int\s*,\s*void\s*[*]\s*[)]/irq_handler_t \1/g' $i || exit $?
done

Signed-Off-By: David Howells <dhowells@redhat.com>
diff --git a/arch/sparc/kernel/sun4m_irq.c b/arch/sparc/kernel/sun4m_irq.c
index 28bcf8e..a654c16 100644
--- a/arch/sparc/kernel/sun4m_irq.c
+++ b/arch/sparc/kernel/sun4m_irq.c
@@ -228,7 +228,7 @@
 	sun4m_timers->cpu_timers[cpu].l14_timer_limit = limit;
 }
 
-static void __init sun4m_init_timers(irqreturn_t (*counter_fn)(int, void *))
+static void __init sun4m_init_timers(irq_handler_t counter_fn)
 {
 	int reg_count, irq, cpu;
 	struct linux_prom_registers cnt_regs[PROMREG_MAX];