ia64: Fix typo in irq_xen.c

Correct spelling "vecotr" to "vector" in
arch/ia64/xen/irq_xen.c
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

arch/ia64/xen/irq_xen.c

@@ -58,7 +58,7 @@ xen_free_irq_vector(int vector)
 
 	irq_op.vector = vector;
 	if (HYPERVISOR_physdev_op(PHYSDEVOP_free_irq_vector, &irq_op))
-		printk(KERN_WARNING "%s: xen_free_irq_vecotr fail vector=%d\n",
+		printk(KERN_WARNING "%s: xen_free_irq_vector fail vector=%d\n",
 		       __func__, vector);
 }