devlink: fix port dump cmd type

Unlike other commands, due to a c&p error, port dump fills-up cmd with
wrong value, different from port-get request cmd, port-get doit reply
and port notification.

Fix it by filling cmd with value DEVLINK_CMD_PORT_NEW.

Skimmed through devlink userspace implementations, none of them cares
about this cmd value. Only ynl, for which, this is actually a fix, as it
expects doit and dumpit ops rsp_value to be the same.

Omit the fixes tag, even thought this is fix, better to target this for
next release.

Fixes: bfcd3a46 ("Introduce devlink infrastructure")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20240220075245.75416-1-jiri@resnulli.us


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