drm/msm/hdmi: fix memory leak after bridge changes

3d3f8b1f ("drm/bridge: make bridge registration independent of drm
flow") resulted that the hdmi bridge object would be leaked at teardown.
Just switch over to devm_kzalloc() as the easy way to solve this.
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/hdmi/hdmi_bridge.c

@@ -25,8 +25,6 @@ struct hdmi_bridge {
 
 void hdmi_bridge_destroy(struct drm_bridge *bridge)
 {
-	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
-	kfree(hdmi_bridge);
 }
 
 static void power_on(struct drm_bridge *bridge)
@@ -209,7 +207,8 @@ struct drm_bridge *hdmi_bridge_init(struct hdmi *hdmi)
 	struct hdmi_bridge *hdmi_bridge;
 	int ret;
 
-	hdmi_bridge = kzalloc(sizeof(*hdmi_bridge), GFP_KERNEL);
+	hdmi_bridge = devm_kzalloc(hdmi->dev->dev,
+			sizeof(*hdmi_bridge), GFP_KERNEL);
 	if (!hdmi_bridge) {
 		ret = -ENOMEM;
 		goto fail;
@@ -220,7 +219,9 @@ struct drm_bridge *hdmi_bridge_init(struct hdmi *hdmi)
 	bridge = &hdmi_bridge->base;
 	bridge->funcs = &hdmi_bridge_funcs;
 
-	drm_bridge_attach(hdmi->dev, bridge);
+	ret = drm_bridge_attach(hdmi->dev, bridge);
+	if (ret)
+		goto fail;
 
 	return bridge;