parisc: Count IPI function call interrupts

Like other platforms, count the number of IPI function call interrupts
and show it in /proc/interrupts.

Signed-off-by: Helge Deller <deller@gmx.de>
diff --git a/arch/parisc/include/asm/hardirq.h b/arch/parisc/include/asm/hardirq.h
index 1a1235a..7f70395 100644
--- a/arch/parisc/include/asm/hardirq.h
+++ b/arch/parisc/include/asm/hardirq.h
@@ -22,6 +22,7 @@ typedef struct {
 	unsigned int irq_stack_usage;
 #ifdef CONFIG_SMP
 	unsigned int irq_resched_count;
+	unsigned int irq_call_count;
 #endif
 	unsigned int irq_unaligned_count;
 	unsigned int irq_fpassist_count;