Wifi scan errors occur in certain circumstances

[markwattier]

There are two circumstances we have found where the following error periodically occurs:

CFG80211-ERROR) wl_cfg80211_sched_scan_start : Invalid sched scan req!! n_ssids:1

One circumstance is when scanning in an environment where there are no APs present.
The other circumstance is on a Yocto Fido system with the 3.10 kernel, and with hostapd added to the system, this occurs after starting and stopping hostapd.