Merge pull request #21 from toandrew/matchstick-b2g2.1

Fixed:Wifi signal does not show dynamically.
Fix dongle cannot be found issue.

In some conditions, the dongle will enter the 'station' mode even its 'hotspot' mode attritube is set to true.

Signed-off-by: Jianmin Zhou <toandrew@infthink.com>