{nl,mac}80211: explicit userspace MPM

Secure or authenticated mesh had the implicit requirement
that the Mesh Peering Management entity be in userspace.
However userspace might want to implement an open MPM as
well, so specify an nl80211 API to indicate this.

TODO: probably need feature flags
TODO: split up disabling auto_open_plinks and the mac80211
      and nl80211 bits into different patches.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
mac80211: mark sdata as OPERATING_GMODE in mesh

Signed-off-by: Ashok Nagarajan <ashok@cozybit.com>
mac80211: return correct mandatory rates when operating in 2.4GHz band

Currently, the function ieee80211_mandatory_rates() doesn't get 802.11g
mandatory rates. This patch will make the function to return correct mandatory
rates when operating in 2.4GHz band.

Signed-off-by: Ashok Nagarajan <ashok@cozybit.com>