Add support for system images that contain the root directory
Add support for system images that contain the root directory

When the root directory is included in system, the assumption that
system is mounted at /system breaks down. Redirect /system to /
in that case.

Change-Id: I8031b32d7cb9ca699c1cc22939e28afce9d1c847

xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build