arm: Use generic idle loop

Use the generic idle loop and replace enable/disable_hlt with the
respective core functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Kevin Hilman <khilman@linaro.org> # OMAP
Link: http://lkml.kernel.org/r/20130321215233.826238797@linutronix.de

arch/arm/mach-gemini/idle.c

@@ -13,9 +13,11 @@ static void gemini_idle(void)
 	 * will never wakeup... Acctualy it is not very good to enable
 	 * interrupts first since scheduler can miss a tick, but there is
 	 * no other way around this. Platforms that needs it for power saving
-	 * should call enable_hlt() in init code, since by default it is
+	 * should enable it in init code, since by default it is
 	 * disabled.
 	 */
+
+	/* FIXME: Enabling interrupts here is racy! */
 	local_irq_enable();
 	cpu_do_idle();
 }