When the frequencies/channels were parsed there was no check that the
resulting band matched what was expected. Now, pass the band object
itself in which has the band set to what is expected.
Add a nested attribute parser. For the first supported attribute
add NL80211_ATTR_SURVEY_INFO.
This allows parsing of nested attributes in the same convenient
way as nl80211_parse_attrs but allows for support of any level of
nested attributes provided that a handler is added for each.
While here, also get rid of netdev_del_station. The only user of this
function was in ap.c and it could easily be replaced by invoking the new
nl80211_build_del_station function. The callback used by
netdev_build_del_station only printed an error and didn't do anything
useful. Get rid of it for now.
As additional frequency info is needed it doesn't make sense to
store a full list of frequencies for every attribute (i.e.
supported, disabled, no-IR, etc).
This changes nl80211_parse_supported_frequencies to take a list
of frequency attributes where each index corresponds to a channel,
and each value can be filled with flag bits to signal any
limitations on that frequency.
wiphy.c then had to be updated to use this rather than the existing
scan_freq_set lists. This, as-is, will break anything using
wiphy_get_disabled_freqs().
