When requesting a TX queue at a given index, warn on out-of-bounds
referencing if the index is greater than the allocated number of
queues.

Specifically, since this function is used heavily in the networking
stack use DEBUG_NET_WARN_ON_ONCE to avoid executing a new branch on
every packet.
Signed-off-by: NNick Child <nnac123@linux.ibm.com>
Link: https://lore.kernel.org/r/20230321150725.127229-2-nnac123@linux.ibm.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>