Revert "PCI/PME: Implement runtime PM callbacks"

This reverts commit 0e157e52.

Heiner reported that the commit in question prevents his network adapter
from triggering PME and waking up when network cable is plugged.

The commit tried to prevent root port waking up from D3cold immediately but
looks like disabing root port PME interrupt is not the right way to fix
that issue so revert it now.  The patch following proposes an alternative
solution to that issue.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=202103


Fixes: 0e157e52 ("PCI/PME: Implement runtime PM callbacks")
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org	# v4.20+