[FIX] sql: Do no consider a table exists if this is a schema table/view
[FIX] sql: Do no consider a table exists if this is a schema table/view

Before this revision, this is not possible to create a model
with a `_table` set to `domains`, for instance.

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo