Add support for single flow dump. The CLIs to dump one rule: flow dump PORT rule ID to dump all: flow dump PORT all Examples: testpmd> flow dump 0 all testpmd> flow dump 0 rule 0 Signed-off-by: Haifei Luo <haifeil@nvidia.com> Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>