net/mlx5e: Re-add support for TX timeout when TX reporter is not valid

When TX reporter was introduced, it took ownership over TX timeout error
handling. this introduced a regression in case TX reporter is not valid
(NET_DEVLINK is not set, or devlink_health_reporter_create failure).

Fix mlx5e_tx_reporter_timeout function so it can be called at all times.

In addition, remove a warning print that indicates that a TX timeout won't
be handled in case of no valid TX reporter.

Fixes: 7d91126b ("net/mlx5e: Add tx timeout support for mlx5e tx reporter")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>