/ ARP cache information, but just flush those using the ip command.
Bringing down wireless interfaces causes wpa_supplicant to fail and
never recover ("wpa_supplicant: l2_packet_receive - recvfrom:
Network is down"). This made associating with a wireless network
rather unreliable and timing-dependant. It seems to work a lot
better now.
svn path=/nixpkgs/trunk/; revision=17514
