ARM: warn if bad IRQ was scheduled

If somebody causes an unexpected bad IRQ, this even will be unnoticed in both dmesg and system logs. If the "bad" IRQ is stuck, the device will just hang silently w/o reporting anything. Compare this to the generic behaviour (from include/asm-generic/hardirq.h) which prints a message with critical level. So to help everybody, include the same message into ARM-specific ack_bad_irq().

---
 arch/arm/include/asm/hw_irq.h | 1 +
 1 file changed, 1 insertion(+)

index a71b417..af79da4 100644
@@ -8,6 +8,7 @@ static inline void ack_bad_irq(int irq)
 {
 	extern unsigned long irq_err_count;
 	irq_err_count++;
+	pr_crit("unexpected IRQ trap at vector %02x\n", irq);
 }
 
 void set_irq_flags(unsigned int irq, unsigned int flags);

2.1.1