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
Use the correct endian-ness accessor for this TLV field.
(It's coming from firmware and thus it's defined as little-endian.)
Disable this debugging - it's far too verbose when doing TX rate debugging.