PM / devfreq: tegra: Mark ACTMON's governor as immutable

The ACTMON's governor supports only the Tegra's devfreq device and there
is no need to use any other governor, hence let's mark Tegra governor as
immutable to permanently stick it with Tegra's devfreq device.
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

drivers/devfreq/Kconfig

@@ -95,7 +95,6 @@ config ARM_EXYNOS_BUS_DEVFREQ
 config ARM_TEGRA_DEVFREQ
 	tristate "Tegra DEVFREQ Driver"
 	depends on ARCH_TEGRA_124_SOC
-	select DEVFREQ_GOV_SIMPLE_ONDEMAND
 	select PM_OPP
 	help
 	  This adds the DEVFREQ driver for the Tegra family of SoCs.

drivers/devfreq/tegra-devfreq.c

@@ -594,6 +594,7 @@ static struct devfreq_governor tegra_devfreq_governor = {
 	.name = "tegra_actmon",
 	.get_target_freq = tegra_governor_get_target,
 	.event_handler = tegra_governor_event_handler,
+	.immutable = true,
 };
 
 static int tegra_devfreq_probe(struct platform_device *pdev)