Update changelog for OpenZFS 2.2.0 release

This commit updates changelog for native Debian packages for
OpenZFS 2.2.0 release.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Umer Saleem <[email protected]>
Closes #15104

Author: Umer Saleem

contrib/debian/changelog

@@ -1,3 +1,9 @@
+openzfs-linux (2.2.0-0) unstable; urgency=low
+
+  * OpenZFS 2.2.0 is tagged.
+
+ -- Umer Saleem <[email protected]>  Tue, 25 Jul 2023 15:00:00 +0500
+
 openzfs-linux (2.1.99-1) unstable; urgency=low
 
   * Integrate minimally modified Debian packaging from ZFS on Linux