PCI: ZT5550 CPCI Hotplug driver fix

cc: Philip Guo <pg@cs.stanford.edu>

Here's a small patch against the current git tree for the ZT5550 CPCI 
hotplug driver to fix an issue with port freeing that Philip Guo found.

Signed-off-by: Scott Murray <scottm@somanetworks.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>