libnetutil: Check dhcp respose packet length am: 61f25d4a36 am: cee6d38c55 am: 29d054046f am: c29049f4f8 am: 3de04e9840 am: 19702dc499 am: 8191e9ba87
am: 804323c195

Change-Id: I27c237896e46f15c258fda00a9ab23465691cb9e