Update AUTHORS for libaom v3.6.0-rc2

Bug: aomedia:3342
Change-Id: I4b5d69247b3c9bc2cb17516d922cc850f26290d8

AUTHORS

diff --git a/AUTHORS b/AUTHORS
index efb1102..9668dd3 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -141,6 +141,7 @@
 Kavi Ramamurthy <kavii@google.com>
 KO Myung-Hun <komh@chollian.net>
 Krishna Malladi <kmalladi@google.com>
+Kwanghoon Son <kwangson@yahoo.com>
 Kyle Siefring <siekyleb@amazon.com>
 Larisa Markeeva <lmarkeeva@google.com>
 Lauren Partin <lpartin@google.com>