net/mlx5e: Remove optimization which prevented update of ESN state

aso->use_cache variable introduced in commit 8c582ddf ("net/mlx5e: Handle
hardware IPsec limits events") was an optimization to skip recurrent calls
to mlx5e_ipsec_aso_query(). Such calls are possible when lifetime event is
generated:
 -> mlx5e_ipsec_handle_event()
  -> mlx5e_ipsec_aso_query() - first call
  -> xfrm_state_check_expire()
   -> mlx5e_xfrm_update_curlft()
    -> mlx5e_ipsec_aso_query() - second call

However, such optimization not really effective as mlx5e_ipsec_aso_query()
is needed to be called for update ESN anyway, which was missed due to misplaced
use_cache assignment.

Fixes: cee137a6 ("net/mlx5e: Handle ESN update events")
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>