Utils: Rename FileName to FilePath

More in line with QFileInfo terminonlogy which appears to be
best-of-breed within Qt.

Change-Id: I1d051ff1c8363ebd4ee56376451df45216c4c9ab
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/clangtools/clangtoolslogfilereader.h

@@ -29,13 +29,13 @@
 
 #include <QList>
 
-namespace Utils { class FileName; }
+namespace Utils { class FilePath; }
 
 namespace ClangTools {
 namespace Internal {
 
 QList<Diagnostic> readSerializedDiagnostics(const QString &filePath,
-                                            const Utils::FileName &projectRootDir,
+                                            const Utils::FilePath &projectRootDir,
                                             const QString &logFilePath,
                                             QString *errorMessage);