i386: add support for picopower irq router

Add support for PicoPower PT86C523 IRQ router to be used with the in-kernel
yenta driver for CardBus.  With this patch cardbus works on e.g.  Dell
Latitude XPi P150CD.

Initial patch for kernel 2.4 series by Sune Mølgaard
http://molgaard.org/code/linux-2.4.31-picopower.patch

Ported to 2.6.20 by Chmouel Boudjnah (http://www.chmouel.com)

Testing and confirmation that it works by Austin Acton

Cleaned up a little for inclusion in a 2.6.21-rc7 based kernel.

Added some more cleanups according to CodingStyle, as noted by
Randy Dunlap on LKML.

[akpm@linux-foundation.org: build fixes]
Signed-off-by: Thomas Backlund <tmb@mandriva.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>