CVE-2026-98337: wifi: mac80211: don't start a ROC while scanning

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: don't start a ROC while scanning

The ROC work can be pending when a scan starts (which requires ROC list to be empty, but that's possible), and then a new ROC can be added to the list and the work will pick it up.

Avoid starting that ROC if a scan made it between things, as otherwise we'll hit a warning later:

WARNING: net/mac80211/offchannel.c:404 at ieee80211startnextroc+0x256/0x2d0 Workqueue: eventsunbound cfg80211wiphywork Call Trace: ieee80211scancompleted+0x4fd/0xe40 net/mac80211/scan.c:537 ieee80211scanwork+0x472/0x1ff0 net/mac80211/scan.c:1193 cfg80211wiphywork+0x410/0x570 net/wireless/core.c:513