Merge branch 'bugfix/set_channel_in_NULL_mode' into 'master'

fix the bug for setting channel when Wi-Fi in NULL mode

Closes WIFI-1688, WIFI-1689, and WIFI-1704

See merge request espressif/esp-idf!7700
This commit is contained in:
Jiang Jiang Jian
2020-03-02 14:10:35 +08:00