net/atlantic: remove extra error check
net/atlantic: remove extra error check

Found by Coverity scan - dead code

Coverity issue: 337665
Fixes: 7943ba05f67c ("net/atlantic: add link status and interrupt management")
Cc: stable@dpdk.org

Signed-off-by: Igor Russkikh <84bb31e89044ad5cf75616997932933f48af3f9a@aquantia.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk