drm/i915/display: move IPC under display wm sub-struct

Move display IPC related member under drm_i915_private display
sub-struct.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/04ccaaceee9293e5a6c75761ba9d36792c36f095.1662983005.git.jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_display_core.h

@@ -239,6 +239,8 @@ struct intel_wm {
 	 * crtc_state->wm.need_postvbl_update.
 	 */
 	struct mutex wm_mutex;
+
+	bool ipc_enabled;
 };
 
 struct intel_display {

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

@@ -3122,7 +3122,7 @@ void intel_wm_state_verify(struct intel_crtc *crtc,
 
 bool skl_watermark_ipc_enabled(struct drm_i915_private *i915)
 {
-	return i915->ipc_enabled;
+	return i915->display.wm.ipc_enabled;
 }
 
 void skl_watermark_ipc_update(struct drm_i915_private *i915)
@@ -3162,7 +3162,7 @@ void skl_watermark_ipc_init(struct drm_i915_private *i915)
 	if (!HAS_IPC(i915))
 		return;
 
-	i915->ipc_enabled = skl_watermark_ipc_can_enable(i915);
+	i915->display.wm.ipc_enabled = skl_watermark_ipc_can_enable(i915);
 
 	skl_watermark_ipc_update(i915);
 }
@@ -3506,7 +3506,7 @@ static ssize_t skl_watermark_ipc_status_write(struct file *file,
 		if (!skl_watermark_ipc_enabled(i915) && enable)
 			drm_info(&i915->drm,
 				 "Enabling IPC: WM will be proper only after next commit\n");
-		i915->ipc_enabled = enable;
+		i915->display.wm.ipc_enabled = enable;
 		skl_watermark_ipc_update(i915);
 	}