ARM: fix /proc/interrupts formatting

As per x86, align the initial column according to how many IRQs we
have.  Also, provide an english explaination for the 'LOC:' and
'IPI:' lines.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/mach/irq.h b/arch/arm/include/asm/mach/irq.h
index ce3eee9f..2bc47fb 100644
--- a/arch/arm/include/asm/mach/irq.h
+++ b/arch/arm/include/asm/mach/irq.h
@@ -20,7 +20,7 @@
 extern unsigned int arch_nr_irqs;
 extern void (*init_arch_irq)(void);
 extern void init_FIQ(void);
-extern int show_fiq_list(struct seq_file *, void *);
+extern int show_fiq_list(struct seq_file *, int);
 
 /*
  * This is for easy migration, but should be changed in the source