net/mlx5e: Use the correct delete call on offloaded TC encap entry detach

We wrongly direcly invoke hlist_del_rcu() and not hash_del_rcu() which
does a slightly different call now and may change later, fix that.

Fixes: a54e20b4

 ('net/mlx5e: Add basic TC tunnel set action for SRIOV offloads')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reported-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>