[PATCH] ia64: hardirq.h should include smp_lock.h when preempt enabled

As in_atomic() uses kernel_locked() which is in smp_lock.h.

include/asm-ia64/hardirq.h

@@ -89,6 +89,7 @@
 #define irq_enter()		(preempt_count() += HARDIRQ_OFFSET)
 
 #ifdef CONFIG_PREEMPT
+# include <linux/smp_lock.h>
 # define in_atomic()		((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
 # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
 #else