wifi: mac80211: mlme: change flags in ieee80211_determine_chantype()

For MLO we'll need to read flags not directly from the link as
it may not even exist yet if we're just setting up flags for
a secondary link before sending the association request, so
pass the incoming conn_flags separately. Also, while at it,
pass the sdata/link separately as for non-tracking now the
link may be NULL.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>