thunderbolt: Replace deprecated PCI functions

pcim_iomap_table() and pcim_request_regions() have been deprecated in
commit e354bb84 ("PCI: Deprecate pcim_iomap_table(),
pcim_iomap_regions_request_all()") and commit d140f80f ("PCI:
Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()").

Replace these functions with pcim_iomap_region().

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>