Merge tag 'video-next-20211228' of https://source.denx.de/u-boot/custodians/u-boot-video into next

- various fixes to the sandbox display support
- support for showing a logo without splash screen config
- support for BMP drawing to depths other than 16bpp
- tests for the different types of supported BMP images
- support showing a logo when running coreboot via qemu