Merge tag 'dm-pull-boo21' of https://source.denx.de/u-boot/custodians/u-boot-dm

Environment tidy-ups
patman 'postfix' support
fix binman test race condition causing a timeout error

# gpg: Signature made Sun 31 Oct 2021 03:36:55 PM EDT
# gpg:                using RSA key B25C0022AF86A7CC1655B6277F173A3E9008ADE6
# gpg:                issuer "[email protected]"
# gpg: Good signature from "Simon Glass <[email protected]>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: B25C 0022 AF86 A7CC 1655  B627 7F17 3A3E 9008 ADE6