support Visual Studio 2015

Task-number: QTBUG-46344
Change-Id: I49c3e2776e65cc83d40d1f5ab3be1365d17242d1
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>

src/plugins/debugger/cdb/cdbengine.cpp

@@ -761,6 +761,8 @@ static QByteArray msvcRunTime(const Abi::OSFlavor flavour)
         return "MSVCR110";
     case Abi::WindowsMsvc2013Flavor:
         return "MSVCR120";
+    case Abi::WindowsMsvc2015Flavor:
+        return "MSVCR140";
     default:
         break;
     }