[PARISC] Introduce DINO_LOCAL_IRQS and use it for gsc_find_local_irq

Fix dino by using DINO_LOCAL_IRQS as the limit for gsc_find_local_irq()
instead of the irq itself.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>