Utils: Add a CommandLine::splitArguments() convenience function

... and use it from within new SynchronousProcess functions
taking CommandLine arguments.

Change-Id: I5d7f83727cbb22f03b1a79b1645db95514c66033
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/libs/utils/fileutils.h

@@ -145,6 +145,7 @@ public:
 
     FilePath executable() const { return m_executable; }
     QString arguments() const { return m_arguments; }
+    QStringList splitArguments(OsType osType = HostOsInfo::hostOs()) const;
 
 private:
     FilePath m_executable;