PCI: Leave Apple Thunderbolt controllers on for s2idle or standby

PCI: Leave Apple Thunderbolt controllers on for s2idle or standby

On Macbook 2013, resuming from suspend-to-idle or standby resulted in the
external monitor no longer being detected, a stacktrace, and errors like
this in dmesg:

  pcieport 0000:06:00.0: can't change power state from D3hot to D0 (config space inaccessible)

The reason is that we know how to turn power to the Thunderbolt controller
*off* via the SXIO/SXFP/SXLF methods, but we don't know how to turn power
back on.  We have to rely on firmware to turn the power back on.

When going to the "suspend-to-idle" or "standby" system sleep states,
firmware is not involved either on the suspend side or the resume side, so
we can't use SXIO/SXFP/SXLF to turn the power off.

Skip SXIO/SXFP/SXLF when firmware isn't involved in suspend, e.g., when
we're going to the "suspend-to-idle" or "standby" system sleep states.

Fixes: 1df5172c5c25 ("PCI: Suspend/resume quirks for Apple thunderbolt")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212767
Link: https://lore.kernel.org/r/20210520235501.917397-1-Hi-Angel@yandex.ru
Signed-off-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org