This has always been wrong on v8, but because of the very obscure
odoo/odoo#5797, this seemed to work every time we had single-step
reception.
Please note that this block of XML is noupdate, so for existing
installations you need to change the parent of the reservation location
to something outside your warehouses manually.
Incidentally, this makes the branch green independently of odoo/odoo#5797.
