Update version to 2.2.0

Update xapp-frame-py version to 2.2.0 and update release notes.
E2AP package has been added in version 2.2.0.

Issue-ID : RIC-664

Signed-off-by: Timo Tietavainen <timo.tietavainen@nokia.com>
Change-Id: I23c6795974b0168a3d8c7eb64e60ad07902798e8
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index b35285e..4d12746 100644
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -11,6 +11,11 @@
 and this project adheres to `Semantic Versioning <http://semver.org/>`__.
 
 
+[2.2.0] - 2021-06-23
+--------------------
+* Add E2AP package (`RIC-664 <https://jira.o-ran-sc.org/browse/RIC-664>`_)
+
+
 [2.1.0] - 2021-06-18
 --------------------
 * Add `RNIB <https://gerrit.o-ran-sc.org/r/admin/repos/ric-plt/nodeb-rnib>`_ feature (`RIC-788 <https://jira.o-ran-sc.org/browse/RIC-788>`_)