Input: add tps65218 power button driver

With this driver, we can report KEY_POWER on AM437x SK. This patch has been
tested with said board.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 1da0a20..9591917 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -416,6 +416,16 @@
 	  To compile this driver as a module, choose M here. The module will
 	  be called retu-pwrbutton.
 
+config INPUT_TPS65218_PWRBUTTON
+	tristate "TPS65218 Power button driver"
+	depends on MFD_TPS65218
+	help
+	  Say Y here if you want to enable power buttong reporting for
+	  the TPS65218 Power Management IC device.
+
+	  To compile this driver as a module, choose M here. The module will
+	  be called tps65218-pwrbutton.
+
 config INPUT_TWL4030_PWRBUTTON
 	tristate "TWL4030 Power button Driver"
 	depends on TWL4030_CORE