Fix merge error in CHANGELOG

Author: asomers

CHANGELOG.md

@@ -3,6 +3,17 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](https://semver.org/).
 
+## [Unreleased] - ReleaseDate
+### Added
+
+- Added fine-grained features flags.  Most Nix functionality can now be
+  conditionally enabled.  By default, all features are enabled.
+  (#[1611](https://github.com/nix-rust/nix/pull/1611))
+
+### Changed
+### Fixed
+### Removed
+
 ## [0.23.1] - 2021-12-16
 
 ### Added
@@ -20,17 +31,6 @@ This project adheres to [Semantic Versioning](https://semver.org/).
   `0..FD_SETSIZE`.
   (#[1575](https://github.com/nix-rust/nix/pull/1575))
 
-## [Unreleased] - ReleaseDate
-### Added
-
-- Added fine-grained features flags.  Most Nix functionality can now be
-  conditionally enabled.  By default, all features are enabled.
-  (#[1498](https://github.com/nix-rust/nix/pull/1498))
-
-### Changed
-### Fixed
-### Removed
-
 ## [0.23.0] - 2021-09-28
 ### Added