ARM: at91: fix external interrupts in non-DT case

Management of external interrupts has changed but the
non-DT code has not integrated these changes.
Add a mask to pass external irq specification from SoC
specific code to the at91_aic_init() function.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable <stable@vger.kernel.org> [v3.6]

arch/arm/mach-at91/setup.c

@@ -47,7 +47,7 @@ void __init at91_init_irq_default(void)
 void __init at91_init_interrupts(unsigned int *priority)
 {
 	/* Initialize the AIC interrupt controller */
-	at91_aic_init(priority);
+	at91_aic_init(priority, at91_extern_irq);
 
 	/* Enable GPIO interrupts */
 	at91_gpio_irq_setup();