adding CHANGELOG entry

Author: devnexen

CHANGELOG.md

@@ -25,8 +25,10 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - Added `SO_SETFIB` and `SO_USER_COOKIE` to `nix::sys::socket::sockopt` for FreeBSD.
   ([#2085](https://github.com/nix-rust/nix/pull/2085))
 - Added `SO_RTABLE` for OpenBSD and `SO_ACCEPTFILTER` for FreeBSD/NetBSD to `nix::sys::socket::sockopt`.
-  ([#2085](https://github.com/nix-rust/nix/pull/2085))
+  ([#2088](https://github.com/nix-rust/nix/pull/2088))
 - Removed `flock` from `::nix::fcntl` on Solaris. ([#2082](https://github.com/nix-rust/nix/pull/2082))
+- Added `MAP_ALIGNMENT*` constants and `map_aligned` for NetBSD to `nix::sys::mman`.
+  ([#2090](https://github.com/nix-rust/nix/pull/2090))
 
 ### Changed