fix allow-size-larger-than compiler warning

- lengthMessages_ cannot be negative at this point

Author: svigerske

CoinUtils/src/CoinMessageHandler.cpp

@@ -286,7 +286,7 @@ void CoinMessages::toCompact()
       }
     }
     // space
-    char *temp = new char[lengthMessages_];
+    char *temp = new char[static_cast<unsigned int>(lengthMessages_)];
     CoinOneMessage **newMessage = reinterpret_cast< CoinOneMessage ** >(temp);
     temp += numberMessages_ * CoinSizeofAsInt(CoinOneMessage *);
     CoinOneMessage message;