MN10300: cleanup IRQ affinity setting

The irq_set_affinity handler for the mn10300 cpu pic had some hard-coded IRQs
which were not to be migrated from one cpu to another. This patch cleans those
up by using a combination of IRQF_NOBALANCING and specialized irq chips with
no irq_set_affinity handler. This maintains the previous behavior by using
generic IRQ interfaces rather than hard coding IRQ numbers in the default
irq_set_affinity handler.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>