[FIX] purchase: picking list
[FIX] purchase: picking list

When a product is returned after receiving, the return picking doesn't
appear in the corresponding PO.

opw-686895

bplancher/odoo,bplancher/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,hip-odoo/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,ygol/odoo,dfang/odoo,dfang/odoo,ygol/odoo,dfang/odoo,storm-computers/odoo,laslabs/odoo,hip-odoo/odoo,microcom/odoo,microcom/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,bplancher/odoo,laslabs/odoo,bplancher/odoo,storm-computers/odoo,bplancher/odoo,microcom/odoo,ygol/odoo,bplancher/odoo,hip-odoo/odoo,dfang/odoo,dfang/odoo,storm-computers/odoo,storm-computers/odoo,Elico-Corp/odoo_OCB,ygol/odoo,laslabs/odoo,hip-odoo/odoo,dfang/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,hip-odoo/odoo,microcom/odoo,Elico-Corp/odoo_OCB,laslabs/odoo,microcom/odoo,ygol/odoo,microcom/odoo,ygol/odoo,ygol/odoo,hip-odoo/odoo