nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs

In nfp_flower_spawn_vnic_reprs in the loop if initialization or the
allocations fail memory is leaked. Appropriate releases are added.

Fixes: b9452452 ("nfp: flower: add per repr private data for LAG offload")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>