Utils: Register CommandLine

Needed e.g. in VCS support.

Change-Id: I3a9d64526bc0bf60a77ab154408dfec94cc6ba75
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/utils/fileutils.cpp

@@ -74,6 +74,8 @@ namespace Utils {
 
 */
 
+CommandLine::CommandLine() = default;
+
 CommandLine::CommandLine(const QString &executable)
     : m_executable(FilePath::fromString(executable))
 {}