ethtool: regenerate uapi header from the spec

No functional changes. Mostly the following formatting:
- extra docs
- extra enums
- XXX_MAX = __XXX_CNT - 1 -> XXX_MAX = (__XXX_CNT - 1)
- newlines

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20241204155549.641348-9-sdf@fomichev.me


Signed-off-by: Jakub Kicinski <kuba@kernel.org>