ST7789 color inversion

[tore-espressif]

For reasons unknown (missing git history) ST7789 driver inverts colors by default:

https://github.com/lvgl/lvgl_esp32_drivers/blob/master/lvgl_tft/st7789.c#L68

This has to be made configurable.

This is more-or-less a feature request, as most of the LCD displays support color inversion.

[C47D]

The git history was lost when we moved the lvgl_esp32_drivers content from the lv_port_esp32 repo into it's own repo (this one). I didn't knew on how to do it properly.