The struct pci_driver.suspend_late() hook is one of the legacy PCI power
management callbacks, and there are no remaining users of it.  Remove it.

Link: https://lore.kernel.org/r/20191101204558.210235-7-helgaas@kernel.orgSigned-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>