fix bug. in sta mode, empty passphrase should not use secure auth mode (#5516)
fix bug. in sta mode, empty passphrase should not use secure auth mode (#5516)

* in sta mode, empty passphrase should not use secure auth mode

* use nullptr, camelCase and parenthesis

Lan-Hekary/Arduino,Lan-Hekary/Arduino,esp8266/Arduino,sticilface/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino,Lan-Hekary/Arduino,sticilface/Arduino,esp8266/Arduino,Lan-Hekary/Arduino,Lan-Hekary/Arduino,esp8266/Arduino