[PATCH] x86: constify arch/i386/pci/irq.c

constify structs and add one __initdata.

Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>