Merge tag 'video-2021-07-rc1-2' of https://source.denx.de/u-boot/custodians/u-boot-video

 - search for additional detailed timings in the EDID extension block
 - rework sunxi DE2 driver and accompanying DW-HDMI platform driver
   to drop redundant device specific code, and later use the DT as a
   source of information