Subcontracting upgrade 3.0/3.1 to 4.x

Element MatSub in the MRP Requirement (MD04) is calculated wrongly. Apply note 121238. Run the OSS note program ZZSUBC40 once and the problems is solved. In the new version, stocks are tied to the Vendor.

If you want the old logic (3.0x), you can apply note 170597 and the planning will not check for Vendor.