x86/irq: Check for VECTOR_UNUSED directly

It's simpler and more intuitive to directly check for VECTOR_UNUSED than
checking whether the other error codes are not set.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/caeaca93-5ee1-cea1-8894-3aa0d5b19241@gmail.com

arch/x86/kernel/irq.c

@@ -251,7 +251,7 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 	} else {
 		ack_APIC_irq();
 
-		if (desc != VECTOR_RETRIGGERED && desc != VECTOR_SHUTDOWN) {
+		if (desc == VECTOR_UNUSED) {
 			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
 					     __func__, smp_processor_id(),
 					     vector);