wpa_supplicant: Call frequency conflict handling during auth

wpa_supplicant: Call frequency conflict handling during auth

Previously, the frequency conflict was handled only during the
association flow. However, some drivers, e.g., mac80211 based
drivers, will fail an authentication request in case that there
are no available channels for use (as they might be used by
other interfaces), and thus the frequency conflict resolution
is never called.

Fix this by calling frequency conflict resolution during
authentication (SME-in-wpa_supplicant) as well.

In addition, get the shared radio frequency from the wpa_s context in
both the SME-in-driver and SME-in-wpa_supplicant cases and not from the
driver.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>