sparc: Use the core irq stats function

Let the core do the irq_desc resolution.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20140223212737.635609567@linutronix.de


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>