drm/vkms: Remove useless call to drm_connector_register/unregister()

The function vkms_output_init() is invoked during the module
initialization, and it handles the creation/configuration of the vkms
essential elements (e.g., connectors, encoder, etc). Among the
initializations, this function tries to initialize a connector and
register it by calling drm_connector_register(). However, inside the
drm_connector_register(), at the beginning of this function there is the
following validation:

 if (!connector->dev->registered)
   return 0;

In this sense, invoke drm_connector_register() after initializing the
connector has no effect because the register field is false. The
connector register happens when drm_dev_register() is invoked; the same
issue exists with drm_connector_unregister(). Therefore, this commit
removes the unnecessary call to drm_connector_register() and
drm_connector_unregister().

Changes since v2:
* Remove unnecessary call to drm_connector_unregister()
* Remove unused label
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190315161142.23gfu32lueyqrmyq@smtp.gmail.com

drivers/gpu/drm/vkms/vkms_output.c

@@ -6,7 +6,6 @@
 
 static void vkms_connector_destroy(struct drm_connector *connector)
 {
-	drm_connector_unregister(connector);
 	drm_connector_cleanup(connector);
 }
 
@@ -71,12 +70,6 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 
 	drm_connector_helper_add(connector, &vkms_conn_helper_funcs);
 
-	ret = drm_connector_register(connector);
-	if (ret) {
-		DRM_ERROR("Failed to register connector\n");
-		goto err_connector_register;
-	}
-
 	ret = drm_encoder_init(dev, encoder, &vkms_encoder_funcs,
 			       DRM_MODE_ENCODER_VIRTUAL, NULL);
 	if (ret) {
@@ -99,9 +92,6 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 	drm_encoder_cleanup(encoder);
 
 err_encoder:
-	drm_connector_unregister(connector);
-
-err_connector_register:
 	drm_connector_cleanup(connector);
 
 err_connector: