Trackball rewrite (#600)

- Implement generic trackball settings
- Refactor T-Deck trackball driver into generic driver at `Drivers/gpio-trackball-module`
- Automatically bind/unbind trackball devices with LVGL
- Automatically load settings for trackball devices on boot

Drivers/gpio-trackball-module/bindings/tactility,gpio-trackball.yaml

@@ -0,0 +1,25 @@
+description: 5-way GPIO trackball (4 directions + click button)
+
+compatible: "tactility,gpio-trackball"
+
+properties:
+  pin-right:
+    type: phandles
+    required: true
+    description: Right-direction GPIO pin
+  pin-up:
+    type: phandles
+    required: true
+    description: Up-direction GPIO pin
+  pin-left:
+    type: phandles
+    required: true
+    description: Left-direction GPIO pin
+  pin-down:
+    type: phandles
+    required: true
+    description: Down-direction GPIO pin
+  pin-click:
+    type: phandles
+    required: true
+    description: Click button GPIO pin