New board: Elecrow CrowPanel Avance 2.8" (#224)

- Added new board
- Extracted ST7789 driver and backlight PWM driver into separate subprojects
- Refactored T-Deck to use the shared driver modules
- Fix bug in WiFi service: searching for APs was broken

Boards/LilygoTdeck/Source/hal/TdeckDisplay.h

@@ -15,7 +15,7 @@ private:
 
 public:
 
-    std::string getName() const final { return "ST7780"; }
+    std::string getName() const final { return "ST7789"; }
     std::string getDescription() const final { return "SPI display"; }
 
     bool start() override;