C++: Change note for *= and constant *

Author: jbj

change-notes/1.26/analysis-cpp.md

@@ -20,4 +20,4 @@ The following changes in version 1.26 affect C/C++ analysis in all applications.
 
 * The models library now models more taint flows through `std::string`.
 * The `SimpleRangeAnalysis` library now supports multiplications of the form
-  `e1 * e2` when `e1` and `e2` are unsigned.
+  `e1 * e2` and `x *= e2` when `e1` and `e2` are unsigned or constant.