irq.c is missing the inclusion of asm/io.h, which causes
readb() and writeb() the be undefined.
Signed-off-by: Sven Hartge <hartge@ds9.argh.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>