Support 4 channel mic in Windows Core Audio

BUG=webrtc:7220

Review-Url: https://codereview.webrtc.org/2712743004
Cr-Commit-Position: refs/heads/master@{#16940}
diff --git a/AUTHORS b/AUTHORS
index a1c8a67..e014bfb 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -18,6 +18,7 @@
 Graham Yoakum <gyoakum@skobalt.com>
 Jake Hilton <jakehilton@gmail.com>
 James H. Brown <jbrown@burgoyne.com>
+Jens Nielsen <jens.nielsen@berotec.se>
 Jiawei Ou <jiawei.ou@gmail.com>
 Jie Mao <maojie0924@gmail.com>
 Luke Weber <luke.weber@gmail.com>