usb:composite: USB Mass Storage - f_mass_storage.c from Linux kernel

The f_mass_storage.c source file from v2.6.36 Linux kernel.

commit 8876f5e7d3b2a320777dd4f6f5301d474c97a06c
Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
Date:   Mon Jun 21 13:57:09 2010 +0200

USB: gadget: f_mass_storage: added eject callback

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Piotr Wilczek <p.wilczek@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Marek Vasut <marek.vasut@gmail.com>