Add descriptive error messages to common ethtool failures to be more
user friendly.

Update `nfp_net_coalesce_para_check` to only check one argument, which
facilitates unique error messages.

Additionally, three error codes are updated to `EOPNOTSUPP` to reflect
that these operations are not supported.
Signed-off-by: Ryno Swart <ryno.swart@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Link: https://lore.kernel.org/r/20231206151209.20296-2-louis.peens@corigine.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>