The of_iounmap is at the out_unmap label, but at that point up has already
been freed. The free cannot be moved to the out_unmap label, because that
label is reachable from cases where up should not be freed. So the call to
of_iounmap is just duplicated, and the goto converted to a return.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)