usb: typec: silence a static checker warning

Smatch complains about a potential missing error code:

    drivers/usb/typec/port-mapper.c:168 typec_link_port()
    warn: missing error code 'ret'

This is a false positive and returning zero is intentional.  Let's
re-arrange the code to silence the warning and make the intent more
clear.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YHadaACH8Mq/10F7@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>