Merge U-Boot v2020.01 into master

Merges away nearly all of our Android changes; we are left with a few
recent changes to add hard disk support to the env subsystem and some
hacks for rockpi4.

Bug: 147107640
Change-Id: Ifa62cc29e44d46066434e5af199c7b2108910024
Signed-off-by: Alistair Delva <adelva@google.com>