All architectures must implement IRQ functions.  Since various
dependencies on !S390 were removed, there are various drivers that can
be selected but will fail to link.  Provide a dummy implementation of
these functions for the !PCI case.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org # 3.9
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>