mesh: Mark wpa_state COMPLETED when mesh join has been performed
In mesh interface, the wpa_supplicant state was either
DISCONNECT/SCANNING in non-secured connection or AUTHENTICATING in
secured connection. The latter prevented the scan. Update the
wpa_supplicant state in mesh to be COMPLETED upon initialization. This
is similar to the P2P GO case.
Signed-off-by: Maital Hahn <maitalm@ti.com>