drm/i915/dsi: Move most things from .disable() into .post_disable() on icl+

encoder->disable() is supposed to happen before the pipe/transcoder
gets disabled. The icl+ DSI code screwed that up and put most things
(including the transcoder disable itself) into  encoder->disable().
Follow the common rules and hoist most things into the
encoder->post_disable() hook.
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230608203057.23759-9-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/display/icl_dsi.c

@@ -1395,11 +1395,20 @@ static void gen11_dsi_disable(struct intel_atomic_state *state,
 			      const struct drm_connector_state *old_conn_state)
 {
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
-	struct intel_crtc *crtc = to_intel_crtc(old_conn_state->crtc);
 
 	/* step1: turn off backlight */
 	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_OFF);
 	intel_backlight_disable(old_conn_state);
+}
+
+static void gen11_dsi_post_disable(struct intel_atomic_state *state,
+				   struct intel_encoder *encoder,
+				   const struct intel_crtc_state *old_crtc_state,
+				   const struct drm_connector_state *old_conn_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(old_conn_state->crtc);
+
+	intel_crtc_vblank_off(old_crtc_state);
 
 	/* step2d,e: disable transcoder and wait */
 	gen11_dsi_disable_transcoder(encoder);
@@ -1420,14 +1429,6 @@ static void gen11_dsi_disable(struct intel_atomic_state *state,
 
 	/* step4: disable IO power */
 	gen11_dsi_disable_io_power(encoder);
-}
-
-static void gen11_dsi_post_disable(struct intel_atomic_state *state,
-				   struct intel_encoder *encoder,
-				   const struct intel_crtc_state *old_crtc_state,
-				   const struct drm_connector_state *old_conn_state)
-{
-	intel_crtc_vblank_off(old_crtc_state);
 
 	intel_dsc_disable(old_crtc_state);