net: remove dev_pick_tx_cpu_id()

dev_pick_tx_cpu_id() has been introduced with two users by
commit a4ea8a3d ("net: Add generic ndo_select_queue functions").
The use in AF_PACKET has been removed in 2019 by
commit b71b5837 ("packet: rework packet_pick_tx_queue() to use common code selection")
The other user was a Netlogic XLP driver, removed in 2021 by
commit 47ac6f56 ("staging: Remove Netlogic XLP network driver").

It's relatively unlikely that any modern driver will need an
.ndo_select_queue implementation which picks purely based on CPU ID
and skips XPS, delete dev_pick_tx_cpu_id()

Found by code inspection.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20240906161059.715546-1-kuba@kernel.org


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