net/ark: fix return value of null not checked
net/ark: fix return value of null not checked

Coverity issue: 144517
Fixes: 1131cbf0fb2b ("net/ark: stub PMD for Atomic Rules Arkville")
Cc: stable@dpdk.org

Signed-off-by: John Miller <8c3e694821b089e49385d637347abd0ef3d091ca@atomicrules.com>

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