Input: stmpe-ts - enforce device tree only mode

The STMPE MFD is only used with device tree configured systems (and STMPE
MFD core depends on OF), so force the configuration to come from device
tree only.

Tested-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 547f67d..a398d63 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -958,6 +958,7 @@
 config TOUCHSCREEN_STMPE
 	tristate "STMicroelectronics STMPE touchscreens"
 	depends on MFD_STMPE
+	depends on (OF || COMPILE_TEST)
 	help
 	  Say Y here if you want support for STMicroelectronics
 	  STMPE touchscreen controllers.