wifi: cfg80211: fully move wiphy work to unbound workqueue

Previously I had moved the wiphy work to the unbound
system workqueue, but missed that when it restarts and
during resume it was still using the normal system
workqueue. Fix that.

Fixes: 91d20ab9

 ("wifi: cfg80211: use system_unbound_wq for wiphy work")
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240522124126.7ca959f2cbd3.I3e2a71ef445d167b84000ccf934ea245aef8d395@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>