This patch refactors the layer 2 update frame sending logic into two routines. Both...

This patch refactors the layer 2 update frame sending logic into two routines.  Both RNR and XID frames are sent to update bridges.  The RNR is probably not the best way to update L2 bridges.  It's basically telling the bridges and switches that the MAC is not able to receive traffic (i.e. congested or down) and we never send any other L2 packets to counteract any side effects of this.  I also found that it didn't seem to be updating every MAC table on every bridge.  XID, however, is the correct way, according to my research and we send XID to inform the bridges of the new location of the MAC as dictated by the standards.  I left the RNR in there for good measure, since it doesn't appear to have any ill effects for anyone.  (Hostapd ALSO sends XID when you are using hostapd... the redundancy is harmless and allows madwifi to operate correctly when using open or WEP protected modes without hostapd).

git-svn-id: http://madwifi-project.org/svn/madwifi/trunk@3134 0192ed92-7a03-0410-a25b-9323aeb14dbd