PM / devfreq: governors: add GPL module license and allow module build

Add GPL module license and remove the static build
restrictions for building governors. This allows governors now
to be loaded on a need basis and reloaded independently of kernel
build

Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kevin Hilman <khilman@ti.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index f6b0a6e2..0f079be 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -30,7 +30,7 @@
 comment "DEVFREQ Governors"
 
 config DEVFREQ_GOV_SIMPLE_ONDEMAND
-	bool "Simple Ondemand"
+	tristate "Simple Ondemand"
 	help
 	  Chooses frequency based on the recent load on the device. Works
 	  similar as ONDEMAND governor of CPUFREQ does. A device with
@@ -39,7 +39,7 @@
 	  values to the governor with data field at devfreq_add_device().
 
 config DEVFREQ_GOV_PERFORMANCE
-	bool "Performance"
+	tristate "Performance"
 	help
 	  Sets the frequency at the maximum available frequency.
 	  This governor always returns UINT_MAX as frequency so that
@@ -47,7 +47,7 @@
 	  at any time.
 
 config DEVFREQ_GOV_POWERSAVE
-	bool "Powersave"
+	tristate "Powersave"
 	help
 	  Sets the frequency at the minimum available frequency.
 	  This governor always returns 0 as frequency so that
@@ -55,7 +55,7 @@
 	  at any time.
 
 config DEVFREQ_GOV_USERSPACE
-	bool "Userspace"
+	tristate "Userspace"
 	help
 	  Sets the frequency at the user specified one.
 	  This governor returns the user configured frequency if there