net_sched: act_tunnel_key: use RCU in tunnel_key_dump()

Also storing tcf_action into struct tcf_tunnel_key_params
makes sure there is no discrepancy in tunnel_key_act().

No longer block BH in tunnel_key_init() when acquiring tcf_lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250827125349.3505302-4-edumazet@google.com


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