[PATCH 4/4] Add irq debugfs and virq_mapping for getting thevirq to irq host's hwirq mapping list.

[Zhang Wei-r63237]

> 
> Minor nit. Should we be creating a 'powerpc' directory first, and
> putting the 'irq' file under that? Otherwise we risk clashing 
> with some
> generic code that creates a file called 'irq' in debugfs.
> 
> cheers
> 
Hi, Michael,

I've seen some codes in arch/powerpc/kernel/prom.c to create debugfs dir "powerpc". But those codes were enabled by a local macro 'DEBUG'. There is a little problem. Maybe I should change '#ifdef DEBUG' to '#ifdef CONFIG_DEBUG_FS' before the export_flat_device_tree() function in arch/powerpc/kernel/prom.c. How about it?

Thanks!

Best Regards
Zhang Wei