drm/i915/pxp: Enable PXP with MTL-GSC-CS

drm/i915/pxp: Enable PXP with MTL-GSC-CS

Enable PXP with MTL-GSC-CS: add the has_pxp into device info
and increase the debugfs teardown timeouts to align with
new GSC-CS + firmware specs.

Now that we have 3 places that are selecting pxp timeouts
based on tee vs gsccs back-end, let's add a helper.

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230511231738.1077674-9-alan.previn.teres.alexis@intel.com