Merge https://gitlab.denx.de/u-boot/custodians/u-boot-sunxi

Merge https://gitlab.denx.de/u-boot/custodians/u-boot-sunxi

This adds support for devices with R40 dual rank DRAM, and asymmetric
A64 DRAM devices like the Pinephone/3GB.
Also we enable automatic gzipped kernel support, and allow scripted
DT overlay support. The rest of the patches are cleanups, but also
some sunxi-specific preparatory patches for USB3.0 and improved HDMI
support. The bulk of those changes will go through other trees, though.

Build-tested for all 156 sunxi boards, and boot tested on a A64, A20, R40,
H5, H6 and H616 board. USB, SD card, eMMC, HDMI and Ethernet all work
there (where applicable), with the exception of Ethernet on the H5. Since
this is already broken in v2021.04, I will send a separate fix.