For both v1 and v2, support automatic calculation of timing registers for 100khz and 400khz i2c modes. Based on work by Chuck in https://github.com/libopencm3/libopencm3/pull/470 for v1
For both v1 and v2, support automatic calculation of timing registers for 100khz and 400khz i2c modes. Based on work by Chuck in https://github.com/libopencm3/libopencm3/pull/470 for v1