e1000e: Fix error path in link detection

In case of error from e1e_rphy(), the loop will exit early and "success"
will be set to true erroneously.

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>