Update changelog for release v1.22.1

Signed-off-by: Leonard Lyubich <[email protected]>

CHANGELOG.md

@@ -1,5 +1,23 @@
 # Changelog
 
+## [1.22.1] - 2021-01-15
+
+Support changes from NeoFS API v2.2.1 release.
+
+### Added
+
+- Constant prefix of the reserved keys to X-headers (`__NEOFS__`).
+- Constant string key to netmap epoch X-header (`__NEOFS__NETMAP_EPOCH`).
+- Constant string key to netmap lookup depth X-header (`__NEOFS__NETMAP_LOOKUP_DEPTH`).
+
+### Changed
+
+- Linter's configuration in `.golangci.yml`.
+
+### Fixed
+
+- Remarks of the updated linter. 
+
 ## [1.22.0] - 2020-12-30 - Yeouido (여의도, 汝矣島)
 
 Support changes from NeoFS API v2.2.0 "Yeouido" release.
@@ -507,3 +525,4 @@ Initial public release
 [1.21.1]: https://github.com/nspcc-dev/neofs-api-go/compare/v1.21.0...v1.21.1
 [1.21.2]: https://github.com/nspcc-dev/neofs-api-go/compare/v1.21.1...v1.21.2
 [1.22.0]: https://github.com/nspcc-dev/neofs-api-go/compare/v1.21.2...v1.22.0
+[1.22.1]: https://github.com/nspcc-dev/neofs-api-go/compare/v1.22.0...v1.22.1