ARM: at91: at91_dt_defconfig: add TOUCHSCREEN_ADS7846 as a module

Add TOUCHSCREEN_ADS7846 as a module as it is not used on modern boards.

Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com>

Author: cristibirsan

arch/arm/configs/at91_dt_defconfig

@@ -117,7 +117,7 @@ CONFIG_KEYBOARD_QT1070=y
 CONFIG_KEYBOARD_GPIO=y
 # CONFIG_INPUT_MOUSE is not set
 CONFIG_INPUT_TOUCHSCREEN=y
-CONFIG_TOUCHSCREEN_ADS7846=y
+CONFIG_TOUCHSCREEN_ADS7846=m
 CONFIG_TOUCHSCREEN_ATMEL_MXT=y
 # CONFIG_SERIO is not set
 CONFIG_LEGACY_PTY_COUNT=4