imxtools: introduce the new scsitool

imxtools: introduce the new scsitool

It appears that all devices based on the Sigmaltel SDK support a
common vendor specific SCSI interface when in UMS mode. This
applies to the STMP36xx and the STMP37xx. This interface supports
many operations:
- get device info
- get device paritionning
- get janus/drm info
- read/write/allocate/erase any partition
- reset (chip or to updater and/or recovery)
This includes the ability to do a firmware upgrade by rewriting
the firmware partition. The tool currently does mostly nothing
but will be enhanced depending on the reverse engineering efforts
and the use of it. It has been tested on the Fuze+ and the Zen
X-Fi2/3.

Change-Id: Ibd4b2ad364c03ada4f9001573ef4cc87cfb041d1