Migrate devices, create drivers, other improvements & fixes (#574)

Migrated devices to kernel drivers:

- guition-jc3248w535c
- m5stack-core2
- m5stack-cores3
- m5stack-papers3

New drivers:

- axp192-module
- axp2101-module

Fixes:

- Fix SD card LDO for P4 devices
- Updated PowerOff app to work with kernel displays
- Fix for `lvgl_try_lock()` timing
- Fix for touch events with slow updating displays

Improvements:

- `GuiService` now keeps trying to lock to prevent silent failures caused by drivers.
- `GuiService` now uses lvgl-module calls for locking/unlocking
- display driver now has capability `DISPLAY_CAPABILITY_SLOW_REFRESH`

Drivers/axp2101-module/bindings/axp2101-backlight.yaml

@@ -0,0 +1,24 @@
+description: >
+  Backlight driven by a switchable/adjustable AXP2101 LDO. Must be declared as a
+  child node of the axp2101 device it dims. Maps the 0-255 brightness level onto
+  the LDO's [min-millivolt,max-millivolt] voltage range; level 0 disables the LDO outright.
+
+compatible: "axp2101-backlight"
+
+properties:
+  ldo:
+    type: int
+    required: true
+    description: The Axp2101Ldo powering the backlight (e.g. AXP2101_DLDO1)
+  min-millivolt:
+    type: int
+    default: 0
+    description: LDO voltage at brightness level 0 (the LDO is disabled rather than actually set to this value)
+  max-millivolt:
+    type: int
+    required: true
+    description: LDO voltage at the maximum brightness level (255)
+  brightness-default:
+    type: int
+    default: 255
+    description: Default brightness level, applied by set_brightness_default()