fix pylint errors

Also removed some testutils code that must have been dead because it had
rotten.
diff --git a/src/python/oftest/netutils.py b/src/python/oftest/netutils.py
index 613ac66..c7c8051 100644
--- a/src/python/oftest/netutils.py
+++ b/src/python/oftest/netutils.py
@@ -36,6 +36,7 @@
 
 # From netpacket/packet.h
 PACKET_ADD_MEMBERSHIP  = 1
+PACKET_DROP_MEMBERSHIP = 2
 PACKET_MR_PROMISC      = 1
 
 # From bits/socket.h
@@ -47,13 +48,6 @@
   s.close()
   return ifreq
 
-def get_if_hwaddr(iff):
-  addrfamily, mac = struct.unpack("16xh6s8x",get_if(iff,SIOCGIFHWADDR))
-  if addrfamily in [ARPHDR_ETHER,ARPHDR_LOOPBACK]:
-      return str2mac(mac)
-  else:
-      raise Exception("Unsupported address family (%i)"%addrfamily)
-
 def get_if_index(iff):
   return int(struct.unpack("I",get_if(iff, SIOCGIFINDEX)[16:20])[0])