Patch from Ben Dooks

Remove the need for the #ifdefs and place the IRQ handling code for
the s3c2440 into a new file, which is only compiled when the
s3c2440 cpu support is enabled.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>