Merge tag 'video-next' of https://gitlab.denx.de/u-boot/custodians/u-boot-video into next

- migrate remaining imx5/imx6qd boards to DM_VIDEO
- use 'vidconsole' stdout in nitrogen6x upgrade script
- add option for selection of the vidconsole commands
  lcdputs and setcurs
- allow building ipuv3 driver with disabled CONFIG_PANEL
- make backlight and panel drivers optional
- remove useless code from ipuv3 driver
- extend existing DM_VIDEO work-around for console name
  to support 'vga'
- remove non-DM code in ipuv3