ACPI / video: Propagate the error code for acpi_video_register

Report the actual error code from acpi_bus_register_driver(), it may
help future debugging (typically ENODEV as previously reported, but the
unusual cases are where it may help most).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/video.c

@@ -2110,7 +2110,8 @@ static int __init intel_opregion_present(void)
 
 int acpi_video_register(void)
 {
-	int result = 0;
+	int ret;
+
 	if (register_count) {
 		/*
 		 * if the function of acpi_video_register is already called,
@@ -2122,9 +2123,9 @@ int acpi_video_register(void)
 	mutex_init(&video_list_lock);
 	INIT_LIST_HEAD(&video_bus_head);
 
-	result = acpi_bus_register_driver(&acpi_video_bus);
-	if (result < 0)
-		return -ENODEV;
+	ret = acpi_bus_register_driver(&acpi_video_bus);
+	if (ret)
+		return ret;
 
 	/*
 	 * When the acpi_video_bus is loaded successfully, increase