ARM: mach-at91: move special idle code out of line

... and hook it to arm_pm_idle.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c
index 7032dd3..0e80b39 100644
--- a/arch/arm/mach-at91/at91sam9g45.c
+++ b/arch/arm/mach-at91/at91sam9g45.c
@@ -318,6 +318,12 @@
 	}
 };
 
+static void at91sam9g45_idle(void)
+{
+	at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK);
+	cpu_do_idle();
+}
+
 static void at91sam9g45_restart(char mode, const char *cmd)
 {
 	at91_sys_write(AT91_RSTC_CR, AT91_RSTC_KEY | AT91_RSTC_PROCRST | AT91_RSTC_PERRST);
@@ -342,6 +348,7 @@
 
 static void __init at91sam9g45_initialize(void)
 {
+	arm_pm_idle = at91sam9g45_idle;
 	arm_pm_restart = at91sam9g45_restart;
 	at91_extern_irq = (1 << AT91SAM9G45_ID_IRQ0);