This patch fixes wrong dmsg setting when we send out wrb.

If the ttt is not ISCSI_RESERVED_TAG then we should be setting
dmsg=1 so that the completion is done without waiting for a
iscsi level response from the target
Signed-off-by: Jayamohan Kallickal <jayamohan.kallickal@emulex.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>