[FIX] stock/mrp_landed_cost: fix domain no scalable.

Making a dynamic domain with a `allowed_xxx_ids` field is a bad idea
when the domain doesn't filter out the most of records. It can create a
performance issue, if the `allowed_xxx_ids` contains too much ids
(for 70K by example), then a lot of data will be exchange to/from server
for each onchange (500Ko, > 1 sec) which slows down all the form views.

Change it into a static domain, which slows down a little the
search of the picking but the onchange becomes very fast. Also the JS
won't parse anymore a huge `allowed_xxx_ids` fields (the form becomes
smoother).

task-2558097