QSaveFile[win]: remove const from nativeRenameOverwrite

I accidentally copied const from another signature.
It's not changing any members so it's technically fine,
but it leaves a bad feeling and we will change members soon.

Change-Id: Ib0236d7e7dda84834ba35907d75c52cf77fb3843
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 171ac8aa4ef107a7c06163aaeba9a37abffccb09)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/corelib/io/qfsfileengine_p.h

@@ -152,7 +152,7 @@ public:
     bool isSequentialFdFh() const;
 #endif
 #ifdef Q_OS_WIN
-    bool nativeRenameOverwrite(const QString &newName) const;
+    bool nativeRenameOverwrite(const QString &newName);
 #endif
 
     uchar *map(qint64 offset, qint64 size, QFile::MemoryMapFlags flags);

src/corelib/io/qfsfileengine_win.cpp

@@ -396,7 +396,7 @@ bool QFSFileEnginePrivate::nativeIsSequential() const
             || (fileType == FILE_TYPE_PIPE);
 }
 
-bool QFSFileEnginePrivate::nativeRenameOverwrite(const QString &newName) const
+bool QFSFileEnginePrivate::nativeRenameOverwrite(const QString &newName)
 {
     if (fileHandle == INVALID_HANDLE_VALUE)
         return false;