[IA64] iosapic.c: typo ... s/spin_unlock_irq/spin_unlock/

vector sharing patch had a typo ... mismatched spin_lock() with
a spin_unlock_irq().  Fix from Kenji Kaneshige.
Signed-off-by: NTony Luck <tony.luck@intel.com>

arch/ia64/kernel/iosapic.c

@@ -762,7 +762,7 @@ iosapic_register_intr (unsigned int gsi,
 			mask = 0;
 		set_rte(gsi, vector, dest, mask);
 	}
-	spin_unlock_irq(&iosapic_lock);
+	spin_unlock(&iosapic_lock);
 	spin_unlock_irqrestore(&irq_descp(vector)->lock, flags);
 
 	printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",