maxtouch:imx6: Integrate touch driver as module

Since we may need a different driver for touch tuning purposes, it is
advantageous to integrate  the driver as a module.

BCS 746-000889

(cherry picked from commit f88db235)

recipes-kernel/linux/linux-seconorth-5.10/imx6guf/defconfig

@@ -181,7 +181,7 @@ CONFIG_INPUT_TOUCHSCREEN=y
 CONFIG_TOUCHSCREEN_ADS7846=y
 CONFIG_TOUCHSCREEN_AD7879=y
 CONFIG_TOUCHSCREEN_AD7879_I2C=y
-CONFIG_TOUCHSCREEN_ATMEL_MXT=y
+CONFIG_TOUCHSCREEN_ATMEL_MXT=m
 CONFIG_TOUCHSCREEN_EGALAX=y
 CONFIG_TOUCHSCREEN_GOODIX=y
 CONFIG_TOUCHSCREEN_MAX11801=y

recipes-kernel/linux/linux-seconorth-5.10/imx6ullguf/defconfig

@@ -135,7 +135,7 @@ CONFIG_MOUSE_PS2=m
 CONFIG_MOUSE_PS2_ELANTECH=y
 CONFIG_INPUT_TOUCHSCREEN=y
 CONFIG_TOUCHSCREEN_ADS7846=y
-CONFIG_TOUCHSCREEN_ATMEL_MXT=y
+CONFIG_TOUCHSCREEN_ATMEL_MXT=m
 CONFIG_TOUCHSCREEN_EGALAX=y
 CONFIG_TOUCHSCREEN_GOODIX=y
 CONFIG_TOUCHSCREEN_MAX11801=y