Changelog: Add v0.22.0

Author: andreaskurth

CHANGELOG.md

@@ -7,6 +7,15 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## Unreleased
 
+### Added
+
+### Changed
+
+### Fixed
+
+
+## 0.22.0 - 2020-05-01
+
 ### Added
 - `axi_pkg`: Add `bufferable` and `modifiable` helper functions.
 - `axi_dw_converter`: Add support for single-beat *fixed* bursts in the downsizer and for *fixed*