[FIX] mrp: always set a value to computed fiec

Records were filtered so not every record was set in the for loop

Fixes odoo/odoo#38992
Closes odoo/odoo#39071

closes odoo/odoo#39234

X-original-commit: f7d5ba6f
Signed-off-by: Martin Trigaux (mat) <mat@odoo.com>