irqchip/atmel-aic5: Fix irq_retrigger callback return value

The irq_retrigger callback is supposed to return 0 when retrigger
has failed, and a non-zero value otherwise. Tell the core code
that the driver has succedded in using the HW to retrigger the
interrupt.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200310184921.23552-3-maz@kernel.org

drivers/irqchip/irq-atmel-aic5.c

@@ -128,7 +128,7 @@ static int aic5_retrigger(struct irq_data *d)
 	irq_reg_writel(bgc, 1, AT91_AIC5_ISCR);
 	irq_gc_unlock(bgc);
 
-	return 0;
+	return 1;
 }
 
 static int aic5_set_type(struct irq_data *d, unsigned type)