Fix typo (HDFS-5276 -> HDFS-5267) in CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1531500 13f79535-47bb-0310-9956-ffa450edef68
Workaround git eol hell

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1531501 13f79535-47bb-0310-9956-ffa450edef68