cpuidle: big.LITTLE: add Exynos5800 compatible string

Exynos 5800 is big.LITTLE SoC compatible with the 5420.  Add the
compatible string so this driver works on the 5800.

Tested on exynos5800-peach-pi (aka Samsung Chromebook2)

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/cpuidle/cpuidle-big_little.c

@@ -159,6 +159,7 @@ static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int part_id)
 static const struct of_device_id compatible_machine_match[] = {
 	{ .compatible = "arm,vexpress,v2p-ca15_a7" },
 	{ .compatible = "samsung,exynos5420" },
+	{ .compatible = "samsung,exynos5800" },
 	{},
 };