Update changelog.

Author: sletz

changelog.txt

@@ -9,7 +9,7 @@ Copyright GRAME (c) 2014-2022
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 03/23/2022: version 2.5.9
 
-- integrates Faust compiler version 2.40.4
+- integrates Faust compiler version 2.40.4, solving an issue when exporting code
 - based on LLVM 14.0.1 on and OS X and 10.0.0 on Windows 
 - latest version of the Faust libraries