PCI: Fix OF logic in pci_dma_configure()

This patch fixes a bug introduced by previous commit,
which incorrectly checkes the of_node of the end-point device.
Instead, it should check the of_node of the host bridge.

Fixes: 50230713 ("PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>