Added CHANGELOG for 0.22.1.

Review: https://reviews.apache.org/r/32832
diff --git a/CHANGELOG b/CHANGELOG
index efcadfa..79906b6 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,15 @@
+Release Notes - Mesos - Version 0.22.1
+--------------------------------------
+
+* This is a bug fix release.
+
+** Bug
+  * [MESOS-1795] - Assertion failure in state abstraction crashes JVM.
+  * [MESOS-2161] - AbstractState JNI check fails for Marathon framework.
+  * [MESOS-2494] - Clang build broken with "expression result unused" warning.
+  * [MESOS-2583] - Tasks getting stuck in staging.
+
+
 Release Notes - Mesos - Version 0.22.0
 --------------------------------------