Fix clang warnings about copies in range-for constructs

Change-Id: If50553964483626e72a816b1d23fa81b45ed9ca7
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/cmakeprojectmanager/fileapidataextractor.cpp

@@ -276,7 +276,7 @@ QList<CMakeBuildTarget> generateBuildTargets(const PreprocessedData &input,
 
                     // CMake sometimes mixes several shell-escaped pieces into one fragment. Disentangle that again:
                     const QStringList parts = QtcProcess::splitArgs(f.fragment);
-                    for (const QString part : parts) {
+                    for (const QString &part : parts) {
                         // Some projects abuse linking to libraries to pass random flags to the linker, so ignore
                         // flags mixed into a fragment
                         if (part.startsWith("-"))