New kernel drivers and device implementation updates (#561)

- Added modular device support and devicetree bindings for ILI9341, ILI9488, CST816S, XPT2046, and GPIO button input, updating several board configurations for display/touch/backlight/keyboard/battery.
- Added a setting to control deprecated HAL usage (device property + Kconfig).

Devices/elecrow-crowpanel-basic-35/elecrow,crowpanel-basic-35.dts

@@ -7,8 +7,9 @@
 #include <tactility/bindings/esp32_spi.h>
 #include <tactility/bindings/esp32_uart.h>
 #include <tactility/bindings/esp32_sdspi.h>
-#include <tactility/bindings/display_placeholder.h>
-#include <tactility/bindings/pointer_placeholder.h>
+#include <tactility/bindings/esp32_ledc_backlight.h>
+#include <bindings/ili9488.h>
+#include <bindings/xpt2046.h>
 
 / {
 	compatible = "root";
@@ -32,6 +33,15 @@
 		pin-scl = <&gpio0 21 GPIO_FLAG_NONE>;
 	};
 
+	display_backlight {
+		compatible = "espressif,esp32-ledc-backlight";
+		// Off by default so display power-on won't show the screen from before the last power loss.
+		// The display backlight is turned on during the boot process.
+		status = "disabled";
+		pin-backlight = <&gpio0 27 GPIO_FLAG_NONE>;
+		frequency-hz = <512>;
+	};
+
 	spi0 {
 		compatible = "espressif,esp32-spi";
 		host = <SPI2_HOST>;
@@ -41,13 +51,22 @@
 		pin-miso = <&gpio0 33 GPIO_FLAG_NONE>;
 		pin-sclk = <&gpio0 14 GPIO_FLAG_NONE>;
 		max-transfer-size = <65536>;
-	
+
 		display@0 {
-			compatible = "display-placeholder";
+			compatible = "ilitek,ili9488";
+			horizontal-resolution = <320>;
+			vertical-resolution = <480>;
+			color-conversion-buffer-size = <15360>;
+			pixel-clock-hz = <40000000>;
+			pin-dc = <&gpio0 2 GPIO_FLAG_NONE>;
+			backlight = <&display_backlight>;
 		};
 
 		touch@1 {
-			compatible = "pointer-placeholder";
+			compatible = "xptek,xpt2046";
+			x-max = <320>;
+			y-max = <480>;
+			mirror-y;
 		};
 	};