usb: gadget: add support for multiple LUNs

Change-Id: I2d6694639de97c4f261acb752f3e6b15796f0540
msm: HTC: t6: give LUN paths to both storage drives

Change-Id: I926e5f4f4c1bba20237b96da76d719f5317a54eb
Clean up old uneeded files

Change-Id: I484edbf3cd477e94feae4dc8f2f3eb9d411bd947