(split) Fix typo

Reported by:	swildner@DragonFlyBSD.org
(split) Make sure any waiters on the scan results get notified if the scan task
decides to do nothing.

If this isn't done, then a scan request whilst a scan occurs in an active
channel set or a completed channel set will hang.

Tested:

* Intel 5100, STA mode
(split) Merge branch 'CURRENT' (commit '7a2a16a9')