unmount /data on user request for /data/media devices
unmount /data on user request for /data/media devices

Change-Id: I86723215edb8c5d256bdd380ff1806729aa81a8f

Plain-Andy/android_platform_bootable_recovery,Plain-Andy/android_platform_bootable_recovery,kylinmoddev/android_bootable_recovery,Plain-Andy/android_platform_bootable_recovery,kylinmoddev/android_bootable_recovery,Plain-Andy/android_platform_bootable_recovery,kylinmoddev/android_bootable_recovery,kylinmoddev/android_bootable_recovery