drm/i915: Add Wa_1408615072 and Wa_1407596294 to icl,ehl

drm/i915: Add Wa_1408615072 and Wa_1407596294 to icl,ehl

Workaround database indicates we should disable clock gating of both the
vsunit and hsunit.

Bspec: 33450
Bspec: 33451
Cc: stable@kernel.vger.org
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191224012026.3157766-3-matthew.d.roper@intel.com
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>