net80211: able to send Channel Switch Announcement

[Yury Popov]

Now, when connecting to AP in STA+SOFTAP mode, if channel of target AP mismatch to current channel, clients connected to device AP will lost connection because they're don't know where AP goes to.
In 802.11h-2003 introduced feature named CSA (Channel Switch Announcement) (ref: http://read.pudn.com/downloads117/ebook ... h-2003.pdf)
CSA should be sent in beacons and probe/assoc requests.
It seems like libnet80211 is forked from FreeBSD code, where CSA is implemented (and works properly). It will be great if this functionality will be implemented in ESP SDK (any of NONOS or RTOS, both is preferred).

[pratik]

Hello Yuri,

Good suggestion, I will forward this to engineers working on firmware development, thanks!