The point of this menu option is that locked Smart-Art shapes would
preserve the original XML files attached so they could be exported
back to docx with no loss.

The new menu option is located at Options -> Load/Save -> MS Office ->
SmartArt to LibreOffice shapes or reverse.

Change-Id: I6aafc2eb83404ee2c0b8538b2f6fbbbd4363e7d3
Reviewed-on: https://gerrit.libreoffice.org/6138Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Miklos Vajna <vmiklos@collabora.co.uk>