docs: Update for DPDK v1.7.1

Change-Id: I76942753c776616b595e60bbb2ad202beeb28ae5
Signed-off-by: Stephen Finucane <stephen.finucane@intel.com>
Reviewed-by: Kevin Traynor <kevin.traynor@intel.com>
NEWS.md: Update for DPDK 1.7.1

Change-Id: I26361667284f4e8f896832eebac74380c4d1a8dd
Signed-off-by: Stephen Finucane <stephen.finucane@intel.com>
Reviewed-by: Kevin Traynor <kevin.traynor@intel.com>