Instead of using a wrong intialization command sequence for power and frame control, default values after reset are used.

If the controller-specific driver supports multiple controller variants, the variant has to be specified in the configuration parameter set.

If a board definition already used the ST7735 driver, `st7735*.h` header files and `ST7735_*` macros were used in the board definitions to define the default configuration parameter set. For backward compatibility these header files are kept and the `ST7735_*` macros are mapped to the `ST77XX_*` macros if they are defined.