The latest Intel Haswell chipsets have a hardware optimization which
allows on-chip PCI devices to ignore the 10ms delay before entering
or exiting D3 suspend.

This patch implements the optimization as a PCI quirk, since we want
tight control over which devices use it. This way we can test each device
individually to be sure there are no issues before we enable the quirk.
The first set of devices are from the Haswell platform, which includes
every PCI device that is on the northbridge and southbridge.

This patch reduces the Haswell suspend time from 93 ms to 47 ms and resume
time from 160 ms to 64 ms.
Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>