correctly - crashes server !

Creating federated table with connect string containing empty
(zero-length) host name and port is evaluated as 0 (port is
incorrect, omitted or 0) crashes server.

This happens because federated calls strcmp() with NULL pointer.

Fixed by avoiding strcmp() call if hostname is set to NULL.


mysql-test/r/federated.result:
  A test case for BUG#34788.
mysql-test/t/federated.test:
  A test case for BUG#34788.
sql/ha_federated.cc:
  Fixed that parse_url() may call strcmp() with NULL pointer.