net/mlx5e: Fix setup TC ndo

Fail-safe support patches introduced a trivial bug,
setup tc callback is doing a wrong check of the netdevice state,
the fix is simply to invert the condition.

Fixes: 6f9485af ("net/mlx5e: Fail safe tc setup")
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>