Yakkety 0/3 SRU - Fix bugs under virtual scsi server driver for Power

[Tim Gardner]

http://bugs.launchpad.net/bugs/1621088

[PATCH 1/3] UBUNTU: SAUCE: (noup) target/user: Use sense_reason_t in tcmu_queue_cmd_ring
[PATCH 2/3] UBUNTU: SAUCE: (noup) target/user: Return an error if cmd data size is too large
[PATCH 3/3] UBUNTU: SAUCE: (noup) target/user: Fix comments to not refer to data ring

rtg