platform/x86: intel/pmc: Ignore all LTRs during suspend

platform/x86: intel/pmc: Ignore all LTRs during suspend

Add support to ignore all LTRs before suspend and restore the previous
LTR values after suspend. This feature could be turned off with module
parameter ltr_ignore_all_suspend.

LTR value is a mechanism for a device to indicate tolerance to access
the corresponding resource. When system suspends, the resource is not
available and therefore the LTR value could be ignored. Ignoring all
LTR values prevents problematic device from blocking the system to get
to the deepest package state during suspend.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Xi Pardee <xi.pardee@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240906184016.268153-1-xi.pardee@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>