This commit includes the following cleanups:
- The macros `I2C_DEV_1_USED` and `SPI_DEV_1_USED` are now used with the values 0 and 1. This allows to enable but also to disable the second interface even if the board definition enables it by default.
- The second I2C device `I2C_DEV(1)` and the second SPI device `SPI_DEV(1)` are now disabled by default.
- The second SPI device `SPI_DEV(1)` now uses PB5 as default CS signal instead of PA4 to keep PA4 free for ADC or DAC even if `SPI_DEV(1)` is used, for example for the TFT display.
89846f8cea