drm/i915: Set power domain for DDI-E

DDI-E and DDI-A share 4 the same DDI-A lanes.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NXiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -5147,6 +5147,7 @@ static enum intel_display_power_domain port_to_power_domain(enum port port)
 {
 	switch (port) {
 	case PORT_A:
+	case PORT_E:
 		return POWER_DOMAIN_PORT_DDI_A_4_LANES;
 	case PORT_B:
 		return POWER_DOMAIN_PORT_DDI_B_4_LANES;