ethdev: move a queue id check to generic layer

The check of queue_id is done in all drivers implementing
rte_eth_rx_queue_count(). Factorize this check in the generic function.

Note that the nfp driver was doing the check differently, which could
induce crashes if the queue index was too big.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>