Add IA64 support for CPU clock

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/arch-ia64.h b/arch/arch-ia64.h
index a8bb23a..056f636 100644
--- a/arch/arch-ia64.h
+++ b/arch/arch-ia64.h
@@ -33,6 +33,16 @@
 {
 	return ia64_popcnt(bitmask & (~bitmask - 1));
 }
+
+static inline unsigned long get_cpu_clock(void)
+{
+	unsigned long ret;
+
+	__asm__ __volatile__("mov %0=ar.itc" : "=r" (ret) : : "memory");
+	return ret;
+}
+
 #define ARCH_HAVE_FFZ
+#define ARCH_HAVE_CPU_CLOCK
 
 #endif