drm/i915/icl: Fix power well 2 wrt. DC-off toggling order

To enable DC5/6 power well 2 has to be disabled as for previous
platforms, so fix things up.

Bspec: 4234
Fixes: 67ca07e7 ("drm/i915/icl: Add power well support")
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181102182200.17219-1-imre.deak@intel.com

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -2790,6 +2790,12 @@ static const struct i915_power_well_desc icl_power_wells[] = {
 			.hsw.has_fuses = true,
 		},
 	},
+	{
+		.name = "DC off",
+		.domains = ICL_DISPLAY_DC_OFF_POWER_DOMAINS,
+		.ops = &gen9_dc_off_power_well_ops,
+		.id = DISP_PW_ID_NONE,
+	},
 	{
 		.name = "power well 2",
 		.domains = ICL_PW_2_POWER_DOMAINS,
@@ -2801,12 +2807,6 @@ static const struct i915_power_well_desc icl_power_wells[] = {
 			.hsw.has_fuses = true,
 		},
 	},
-	{
-		.name = "DC off",
-		.domains = ICL_DISPLAY_DC_OFF_POWER_DOMAINS,
-		.ops = &gen9_dc_off_power_well_ops,
-		.id = DISP_PW_ID_NONE,
-	},
 	{
 		.name = "power well 3",
 		.domains = ICL_PW_3_POWER_DOMAINS,