Add missing break in COFF parser

Fixes MSVC2015 builds being detected as MSVC2017.

Amends change 0a9414d4.

Task-number: QTBUG-57086
Change-Id: Ia795819d3c915d0be3e57ef16006e29aa98ee266
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

src/plugins/projectexplorer/abi.cpp

@@ -165,6 +165,7 @@ static QList<Abi> parseCoffHeader(const QByteArray &data)
             break;
         case 14:
             flavor = Abi::WindowsMsvc2015Flavor;
+            break;
         case 15:
             flavor = Abi::WindowsMsvc2017Flavor;
             break;