platform/x86: serial-multi-instantiate: Improve dev_err_probe() messaging

Drop duplicate print of returned value in the messages and use pattern
return dev_err_probe(...) where it's possible.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20220709211653.18938-3-andriy.shevchenko@linux.intel.com


Signed-off-by: Hans de Goede <hdegoede@redhat.com>