Thermal: exynos: Add sysfs node supporting exynos's emulation mode.

This patch supports exynos's emulation mode with newly created sysfs node.
Exynos 4x12 (4212, 4412) and 5 series provide emulation mode for thermal
management unit. Thermal emulation mode supports software debug for TMU's
operation. User can set temperature manually with software code and TMU
will read current temperature from user value not from sensor's value.
This patch includes also documentary placed under Documentation/thermal/.

Signed-off-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index c2c77d1..c31b9e4 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -101,6 +101,15 @@
 	  If you say yes here you get support for TMU (Thermal Management
 	  Unit) on SAMSUNG EXYNOS series of SoC.
 
+config EXYNOS_THERMAL_EMUL
+	bool "EXYNOS TMU emulation mode support"
+	depends on EXYNOS_THERMAL
+	help
+	  Exynos 4412 and 4414 and 5 series has emulation mode on TMU.
+	  Enable this option will be make sysfs node in exynos thermal platform
+	  device directory to support emulation mode. With emulation mode sysfs
+	  node, you can manually input temperature to TMU for simulation purpose.
+
 config DB8500_THERMAL
 	bool "DB8500 thermal management"
 	depends on ARCH_U8500