net/cxgbe: skip parsing match items with no spec
net/cxgbe: skip parsing match items with no spec

Skip parsing pattern match items that have no spec. This fixes NULL
dereference when accessing their non-existent spec.

Fixes: ee61f5113b17 ("net/cxgbe: parse and validate flows")
Cc: stable@dpdk.org

Signed-off-by: Rahul Lakkireddy <3a6b348815dc68871481a310c146a6b821ba8f72@chelsio.com>

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