USB: android: Add a new LUN as CD-ROM in mass-storage

Add a new LUN(lun0) which will be exposed as a CD-ROM having the
attributes ro(read-only) & removable as enabled.
This CD-ROM lun is used for saving read-only files which can be used
for system requirements.

Change-Id: Idff5aea8bce233e8b77a4b689323a2f1eb2523e1
Signed-off-by: Rajkumar Raghupathy <raghup@codeaurora.org>