pmac_zilog: Trying to im_free nonexistent area

[Olaf Hering]

Ben,

can you check the error handling in init_pmz() when pmz_register()
register fails? It tries to iounmap ->control_reg, but I dont see how
that can happen.
Also, pmz_init_port() returns always 0, so pmz_probe() doesnt need to
check for non-null.