[IMP] base: improve log for wrong xpath

Before create_multi, in case of invalid syntax used in an XPath, only
the problematic record was displayed. It was not ideal for long
definition but still usable.
Since the views are created using create_multi, the whole file content
is displayed in the error traceback, making it almost impossible to
locate on files with multiple records.

closes odoo/odoo#43542

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