ARM: at91: fix infinite loop in at91_irq_suspend/resume

Fix an infinite loop when suspending or resuming a device with AIC5.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/mach-at91/irq.c

@@ -92,23 +92,21 @@ static int at91_aic_set_wake(struct irq_data *d, unsigned value)
 
 void at91_irq_suspend(void)
 {
-	int i = 0, bit;
+	int bit = -1;
 
 	if (has_aic5()) {
 		/* disable enabled irqs */
-		while ((bit = find_next_bit(backups, n_irqs, i)) < n_irqs) {
+		while ((bit = find_next_bit(backups, n_irqs, bit + 1)) < n_irqs) {
 			at91_aic_write(AT91_AIC5_SSR,
 				       bit & AT91_AIC5_INTSEL_MSK);
 			at91_aic_write(AT91_AIC5_IDCR, 1);
-			i = bit;
 		}
 		/* enable wakeup irqs */
-		i = 0;
-		while ((bit = find_next_bit(wakeups, n_irqs, i)) < n_irqs) {
+		bit = -1;
+		while ((bit = find_next_bit(wakeups, n_irqs, bit + 1)) < n_irqs) {
 			at91_aic_write(AT91_AIC5_SSR,
 				       bit & AT91_AIC5_INTSEL_MSK);
 			at91_aic_write(AT91_AIC5_IECR, 1);
-			i = bit;
 		}
 	} else {
 		at91_aic_write(AT91_AIC_IDCR, *backups);
@@ -118,23 +116,21 @@ void at91_irq_suspend(void)
 
 void at91_irq_resume(void)
 {
-	int i = 0, bit;
+	int bit = -1;
 
 	if (has_aic5()) {
 		/* disable wakeup irqs */
-		while ((bit = find_next_bit(wakeups, n_irqs, i)) < n_irqs) {
+		while ((bit = find_next_bit(wakeups, n_irqs, bit + 1)) < n_irqs) {
 			at91_aic_write(AT91_AIC5_SSR,
 				       bit & AT91_AIC5_INTSEL_MSK);
 			at91_aic_write(AT91_AIC5_IDCR, 1);
-			i = bit;
 		}
 		/* enable irqs disabled for suspend */
-		i = 0;
-		while ((bit = find_next_bit(backups, n_irqs, i)) < n_irqs) {
+		bit = -1;
+		while ((bit = find_next_bit(backups, n_irqs, bit + 1)) < n_irqs) {
 			at91_aic_write(AT91_AIC5_SSR,
 				       bit & AT91_AIC5_INTSEL_MSK);
 			at91_aic_write(AT91_AIC5_IECR, 1);
-			i = bit;
 		}
 	} else {
 		at91_aic_write(AT91_AIC_IDCR, *wakeups);