ACPI: dock: send envp with uevent

Send an env along with our KOBJ_CHANGE uevent so that user space has
the option of checking for that to see if a dock or undock has occurred.

Signed-off-by:  Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/dock.c

@@ -336,11 +336,19 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event)
 static void dock_event(struct dock_station *ds, u32 event, int num)
 {
 	struct device *dev = &dock_device->dev;
+	char event_string[7];
+	char *envp[] = { event_string, NULL };
+
+	if (num == UNDOCK_EVENT)
+		sprintf(event_string, "UNDOCK");
+	else
+		sprintf(event_string, "DOCK");
+
 	/*
 	 * Indicate that the status of the dock station has
 	 * changed.
 	 */
-	kobject_uevent(&dev->kobj, KOBJ_CHANGE);
+	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
 }
 
 /**