uboot-phytec

Merge tag 'for-v2020.04' of https://gitlab.denx.de/u-boot/custodians/u-boot-i2c

i2c changes for 2020.04
- updates the Designware I2C driver
  - get timings from device tree
  - handle units in nanoseconds
  - make sure that the requested bus speed is not exceeded
  - few smaller clean-ups
- adds enums for i2c speed and update drivers which use them
- global_data: remove unused mxc_i2c specific field