[SCSI] iscsi: modify iscsi printk so it can take driver data pointers

Some drivers want to be able to just pass in the driver data pointers
to the iscsi objects. To enable this we need the iscsi printk macro
to cast the object.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

include/scsi/libiscsi.h

@@ -369,9 +369,11 @@ extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 				enum iscsi_param param, char *buf);
+extern void iscsi_suspend_tx(struct iscsi_conn *conn);
 
 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
-	iscsi_cls_conn_printk(prefix, _c->cls_conn, fmt, ##a)
+	iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
+			      fmt, ##a)
 
 /*
  * pdu and task processing