cfg80211: Fix documentation for connect result

The function documentation for cfg80211_connect_bss() and
cfg80211_connect_result() was still claiming that they are used only for
a success case while these functions can now be used to report both
success and various failure cases. The actual use cases were already
described in the connect() documentation.

Update the function specific comments to note the failure cases and also
describe how the special status == -1 case is used in
cfg80211_connect_bss() to indicate a connection timeout based on the
internal implementation in cfg80211_connect_timeout().

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[use tabs for indentation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>