If the peer device was already unbound, then do not attempt to modify
it's resources, otherwise we will crash on dereferencing non-existing
device.

Fixes: 5c65c564 ("net/mlx5e: Support offloading TC NIC hairpin flows")
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>