PCI/PM: Remove pci_pm_complete()

88d26136 ("PM: Prevent runtime suspend during system resume") removed the
pm_runtime_put_sync() from pci_pm_complete() to PM core code
device_complete().

Here the pci_pm_complete() is doing the same work which can be done in
device_complete(), so we can remove it directly.

Signed-off-by: Liu Chuansheng <chuansheng.liu@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>