Update ChangeLog (#656)

Author: solidpixel

Docs/ChangeLog-5x.md

@@ -9,7 +9,7 @@ clocked at 4.2 GHz, running `astcenc` using AVX2 and 6 threads.
 <!-- ---------------------------------------------------------------------- -->
 ## 5.6.0
 
-**Status:** July 2026
+**Status:** Released July 2026
 
 The 5.6.0 release is a minor maintenance release.