QCommandLineOption: prevent aggressive inlining

There is a good chance that in every program, command line options
that have only one name and those that have multiple names are
used. Make better use of the icache by not inlining the Private
ctors into the QCommandLineOption ones.

Saves 400B in text size on Linux GCC 4.9 C++11 release
builds.

Change-Id: I6247d4a2330c5fff75d06f5a40223d972b267e85
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qcommandlineoption.cpp

@@ -41,11 +41,13 @@ QT_BEGIN_NAMESPACE
 class QCommandLineOptionPrivate : public QSharedData
 {
 public:
+    Q_NEVER_INLINE
     explicit QCommandLineOptionPrivate(const QString &name)
         : names(removeInvalidNames(QStringList(name))),
           hidden(false)
     { }
 
+    Q_NEVER_INLINE
     explicit QCommandLineOptionPrivate(const QStringList &names)
         : names(removeInvalidNames(names)),
           hidden(false)