Merge tag 'u-boot-imx-20190426' of git://git.denx.de/u-boot-imx

Porting to DM and i.MX8
------------------------

- warp7 to DM
- kp_imx53 to DM
- Warnings in DT
- MX8QM support
- colibri-imx6ull to DM
- imx7d-pico to DM
- ocotp for MX8