Followup cleanup of https://github.com/odoo/odoo/pull/106620 where Datamatrix of pylibdmtx was replaced with built-in reportlab ECC200DataMatrix option. For stable compatibility, some parts could only be deleted in master, so let's delete them now. closes odoo/odoo#122704 Signed-off-by: Xavier Morel (xmo) <xmo@odoo.com>