net-next: mediatek: set the rx_queue to 0

The get_rps_cpu() function will not do any RPS on the data flow when no
queue is setup and always use the current cpu where the IRQ was handled
to also handle the backlog. As we only have one physical queue we always
set this to 0 unconditionally.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>