genirq: Fix up irq_node() for irq_data changes.

Now that the node ID is tracked in the irq_data structure, update the
irq_node() definition accordingly. This fixes up irq_node() usage under
GENERIC_HARDIRQS_NO_DEPRECATED && SMP.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <20101028023031.GB10365@linux-sh.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>