Added licence boilerplate to our MATLAB files.

The command

tools/checklicenses/checklicenses.py --ignore-suppressions ./webrtc

previously produced this output:
'webrtc/modules/audio_processing/test/apmtest.m' has non-whitelisted license 'UNKNOWN'
'webrtc/modules/audio_processing/transient/test/readDetection.m' has non-whitelisted license 'UNKNOWN'
'webrtc/modules/audio_processing/transient/test/readPCM.m' has non-whitelisted license 'UNKNOWN'
...

This CL adds the WebRTC licence with appropriate year to all our
MATLAB files. All these files were contributed by WebRTC project
members hlundin@, pbos@, niklase@.

BUG=chromium:98592
NOTRY=True

Review-Url: https://codereview.webrtc.org/2781663005
Cr-Commit-Position: refs/heads/master@{#17428}
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/complexityMeasures.m b/webrtc/modules/audio_coding/codecs/ilbc/complexityMeasures.m
index f768194..5c39e36 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/complexityMeasures.m
+++ b/webrtc/modules/audio_coding/codecs/ilbc/complexityMeasures.m
@@ -1,3 +1,13 @@
+%
+%  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+%
+%  Use of this source code is governed by a BSD-style license
+%  that can be found in the LICENSE file in the root of the source
+%  tree. An additional intellectual property rights grant can be found
+%  in the file PATENTS.  All contributing project authors may
+%  be found in the AUTHORS file in the root of the source tree.
+%
+
 clear;
 pack;
 %