iscsit: use the itt_t abstract type

Use the special itt_t type defined by the iscsi headers and the initiator
to make sure it's an opaque value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c
index 8c9955f..ff6fd4f 100644
--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -1475,7 +1475,8 @@
 {
 	struct iscsi_cmd *cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd);
 
-	return cmd->init_task_tag;
+	/* only used for printks or comparism with ->ref_task_tag */
+	return (__force u32)cmd->init_task_tag;
 }
 
 static int iscsi_get_cmd_state(struct se_cmd *se_cmd)