sparc64: Use a seperate counter for timer interrupts and NMI checks, like x86.

This keeps us from having to use kstat_irqs_cpu() from the NMI handler,
the former of which is a profiled function.

Instead we use a currently empty slot in the cpu_data

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c
index 67e1651..f25858e 100644
--- a/arch/sparc/kernel/time_64.c
+++ b/arch/sparc/kernel/time_64.c
@@ -728,6 +728,7 @@
 
 	irq_enter();
 
+	local_cpu_data().irq0_irqs++;
 	kstat_incr_irqs_this_cpu(0, irq_to_desc(0));
 
 	if (unlikely(!evt->event_handler)) {