iscsi: remove the check of task status before transfer datain.
The function spdk_iscsi_transfer_in will handle the task if the
status is not SPDK_SCSI_STATUS_GOOD.
Change-Id: I61155ffa056b3eac551f215d50e1808e5389fdb5
Signed-off-by: cunyinch <cunyin.chang@intel.com>