target: Don't set WBUS16 or SYNC bits in INQUIRY response

SPC-4 says about the WBUS16 and SYNC bits:

    The meanings of these fields are specific to SPI-5 (see 6.4.3).
    For SCSI transport protocols other than the SCSI Parallel
    Interface, these fields are reserved.

We don't have a SPI fabric module, so we should never set these bits.
(The comment was misleading, since it only mentioned Sync but the
actual code set WBUS16 too).

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>