ARM: omap2plus_defconfig: enable TPS65218 power button

Enable tps65218 power button driver by default as
a dynamically linked module so AM437x SK can report
power button presses.
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/configs/omap2plus_defconfig

@@ -182,6 +182,7 @@ CONFIG_TOUCHSCREEN_EDT_FT5X06=m
 CONFIG_TOUCHSCREEN_TSC2005=m
 CONFIG_TOUCHSCREEN_TSC2007=m
 CONFIG_INPUT_MISC=y
+CONFIG_INPUT_TPS65218_PWRBUTTON=m
 CONFIG_INPUT_TWL4030_PWRBUTTON=m
 CONFIG_SERIO=m
 # CONFIG_LEGACY_PTYS is not set