updater: looser throw specification for what() of exception

Change-Id: Ia73dea0cb845e1fb9a743157bbeadbcfeb1d3627

desktop/source/app/updater.cxx

@@ -56,7 +56,7 @@ public:
     {
     }
 
-    virtual const char* what() const override
+    virtual const char* what() const  throw() override
     {
         return maStr.getStr();
     }