drm/panel/lg-sw43408: Use refcounted allocation in place of devm_kzalloc()

Move to using the new API devm_drm_panel_alloc() to allocate the
panel. In the call to the new API, avoid using explicit type and use
__typeof() for more type safety.

Signed-off-by: Anusha Srivatsa <asrivats@redhat.com>
Link: https://lore.kernel.org/r/20250710-b4-driver-convert-last-part-july-v1-6-de73ba81b2f5@redhat.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>

Author: anushasrivats

drivers/gpu/drm/panel/panel-lg-sw43408.c

@@ -246,8 +246,6 @@ static int sw43408_add(struct sw43408_panel *ctx)
 
 	ctx->base.prepare_prev_first = true;
 
-	drm_panel_init(&ctx->base, dev, &sw43408_funcs, DRM_MODE_CONNECTOR_DSI);
-
 	drm_panel_add(&ctx->base);
 	return ret;
 }
@@ -257,9 +255,11 @@ static int sw43408_probe(struct mipi_dsi_device *dsi)
 	struct sw43408_panel *ctx;
 	int ret;
 
-	ctx = devm_kzalloc(&dsi->dev, sizeof(*ctx), GFP_KERNEL);
-	if (!ctx)
-		return -ENOMEM;
+	ctx = devm_drm_panel_alloc(&dsi->dev, __typeof(*ctx), base,
+				   &sw43408_funcs, DRM_MODE_CONNECTOR_DSI);
+
+	if (IS_ERR(ctx))
+		return PTR_ERR(ctx);
 
 	dsi->mode_flags = MIPI_DSI_MODE_LPM;
 	dsi->format = MIPI_DSI_FMT_RGB888;