Add the unwind information to irq_entry so we can pass through it when

unwinding the stack.

sys/arm/arm/irq_dispatch.S

@@ -89,6 +89,7 @@ AST_LOCALS
 ASENTRY_NP(irq_entry)
 	sub	lr, lr, #0x00000004	/* Adjust the lr */
 	PUSHFRAMEINSVC			/* Push an interrupt frame */
+	UNWINDSVCFRAME
 	mov	r0, sp			/* arg for dispatcher */
 
 	mov	r1, #0