Staging: ipack/bridges/tpci200: reorder the iounmap and pci_release_region

Move iounmap and pci_release_region to tpci200_unregister(), as it is the place
where the clean-up of the device is done.

Also, renamed iounmap() to pci_iounmap() as the mapped region was requested
from PCI bus.

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>