scsi: report well known logical units

REPORT LUNS command has "SELECT REPORT" field which controls what type of
logical units to be reported by device server. According to UFS device
standard, if this field is set to 0, REPORT LUNS would report only report
standard logical units. If it's set to 1 then it would report only well
known logical unit and if it's set to 2 then device would report both
standard and well known logical units.

This change allows the SCSI LLD (Low Level Driver) to choose which type
of logical units should be detected.

Change-Id: I6a24abc44e7e77c218685c4992c4f0ecca2a058e
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>