x86: SGI UV: Fix irq affinity for hub based interrupts

This patch fixes handling of uv hub irq affinity.  IRQs with ALL or
NODE affinity can be routed to cpus other than their originally
assigned cpu.  Those with CPU affinity cannot be rerouted.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20090930160259.GA7822@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>