[FIX] mrp: change BOM

- Create a MO for Product A with quantity to produce of 2
- Produce 1
- Open the associated BOM, and add a line to the bom
- Go back to the MO and try to update the qty to produce to 1

Traceback: division by 0

opw-1838006

addons/mrp/models/mrp_production.py

@@ -349,7 +349,7 @@ class MrpProduction(models.Model):
             source_location = routing.location_id
         else:
             source_location = self.location_src_id
-        original_quantity = self.product_qty - self.qty_produced
+        original_quantity = (self.product_qty - self.qty_produced) or 1.0
         data = {
             'sequence': bom_line.sequence,
             'name': self.name,