[U-Boot] Signed-off-by rules for U-Boot

[Stephen Warren]

Does U-Boot follow the same Signed-off-by procedures as the Linux
kernel, or is s-o-b only relevant in U-Boot for the initial patch
submitter, and not maintainers?

I ask because there are a bunch of patches of mine that got applied
without the maintainer adding their S-o-b when applying them, which
would be very unusual for Linux, but perhaps it's normal for U-Boot?

Some likely non-exhaustive examples are:

2813006fecda usb: ci_udc: allow multiple buffer allocs per ep
66b88b07cdab usb: ums: add error handling for failed registration
264e0e591bbd config: enable CMD_BMP when API+LCD is enabled
53eb768dfb97 aes: make apply_cbc_chain_data non-static

Yet others did get a maintainer s-o-b:

d381294aef4a ARM: tegra: pack pinmux data tables tighter
def816a2ba87 mmc: set rca to 1 for MMC cards
91171091c673 ARM: tegra: make use of negative ENV_OFFSET on NVIDIA...
6ab6a650a418 disk: initialize name/part fields when returning a whole...
c75942c7b792 sf: winbond: fix page_size

It seems like it mostly varies by maintainer.