net: ethtool: add ring parameter filtering

While the devmem is running, the tcp-data-split and
hds-thresh configuration should not be changed.
If user tries to change tcp-data-split and threshold value while the
devmem is running, it fails and shows extack message.

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Link: https://patch.msgid.link/20250114142852.3364986-5-ap420073@gmail.com


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