drm/i915/psr: Apply Wa_14015648006 for all display 14 steppings

According to recent Bspec Wa 14015648006 has to be applied for all display
14 steppings.

Bspec: 66624

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829094435.2100669-1-jouni.hogander@intel.com