Support 135*240 and 240*240 TFT

[jeroenvermeulen]

Cleaned up code, defines instead of overrides.

Description:

Related issue (if applicable): fixes #28

Checklist:

• [x] The pull request is done against the latest ~dev~ universal branch
• [x] Only relevant files were touched
• [x] Only one feature/fix was added per PR.
• [ ] The code change is tested and works on Tasmota core ESP8266 V.2.7.4.1
• [x] The code change is tested and works on core ESP32 V.2.1.0
• [x] I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass

[jeroenvermeulen]

There are some compiler warnings, I have to say I am not a C++ expert so it would take me a lot of research to understand and solve these:

lib/lib_display/Arduino_ST7789-gemu-1.0/Arduino_ST7789.cpp: In member function 'void Arduino_ST7789::init(uint16_t, uint16_t)':
lib/lib_display/Arduino_ST7789-gemu-1.0/Arduino_ST7789.cpp:556:21: warning: narrowing conversion of '((((int)((Arduino_ST7789*)this)->Arduino_ST7789::<anonymous>.Renderer::<anonymous>.Adafruit_GFX::_width) + ((int)((Arduino_ST7789*)this)->Arduino_ST7789::_xstart)) >> 8)' from 'int' to 'uint8_t {aka unsigned char}' inside { } [-Wnarrowing]
    (_width+_xstart) >> 8,
                     ^
lib/lib_display/Arduino_ST7789-gemu-1.0/Arduino_ST7789.cpp:557:21: warning: narrowing conversion of '((((int)((Arduino_ST7789*)this)->Arduino_ST7789::<anonymous>.Renderer::<anonymous>.Adafruit_GFX::_width) + ((int)((Arduino_ST7789*)this)->Arduino_ST7789::_xstart)) & 255)' from 'int' to 'uint8_t {aka unsigned char}' inside { } [-Wnarrowing]
    (_width+_xstart) & 0xFF,   // XEND = 240
                     ^
lib/lib_display/Arduino_ST7789-gemu-1.0/Arduino_ST7789.cpp:560:25: warning: narrowing conversion of '((((int)((Arduino_ST7789*)this)->Arduino_ST7789::<anonymous>.Renderer::<anonymous>.Adafruit_GFX::_height) + ((int)((Arduino_ST7789*)this)->Arduino_ST7789::_ystart)) >> 8)' from 'int' to 'uint8_t {aka unsigned char}' inside { } [-Wnarrowing]
       (_height+_ystart) >> 8,
                         ^
lib/lib_display/Arduino_ST7789-gemu-1.0/Arduino_ST7789.cpp:561:22: warning: narrowing conversion of '((((int)((Arduino_ST7789*)this)->Arduino_ST7789::<anonymous>.Renderer::<anonymous>.Adafruit_GFX::_height) + ((int)((Arduino_ST7789*)this)->Arduino_ST7789::_xstart)) & 255)' from 'int' to 'uint8_t {aka unsigned char}' inside { } [-Wnarrowing]
    (_height+_xstart) & 0xFF, // YEND = 240
                      ^