ARM: GIC: fix irq_trigger return

The genirq layer expects a 0 in case of failure. The current code is
returning -ENXIO for an error.

Fix it.

Change-Id: I0985f12477d472f4fbef525f7b04fed9bf593686
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Ajay Dudani <adudani@codeaurora.org>
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index bbd6c63..9dd4347 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -367,7 +367,8 @@
 	if (gic_arch_extn.irq_retrigger)
 		return gic_arch_extn.irq_retrigger(d);
 
-	return -ENXIO;
+	/* the genirq layer expects 0 for a failure */
+	return 0;
 }
 
 #ifdef CONFIG_SMP