net: ipa: don't pass tag value to ipa_cmd_ip_tag_status_add()

We only send a tagged packet from the AP->command TX endpoint when
we're clearing the hardware pipeline.  And when we receive the
tagged packet we don't care what the actual tag value is.

Stop passing a tag value to ipa_cmd_ip_tag_status_add(), and just
encode 0 as the tag sent.  Fix the function that encodes the tag so
it uses the proper byte ordering.

Signed-off-by: Alex Elder <elder@linaro.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>