[SCSI] scsi_transport_iscsi: Add host statistics support

Add transport_iscsi hooks to get aggregate host statistics.
The statistics include MAC, TCP/IP & iSCSI statistics.

Signed-off-by: Lalit Chandivade <lalit.chandivade@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 2ac11fe..88640a4 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -166,6 +166,7 @@
 	int (*logout_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
 				 struct iscsi_bus_flash_conn *fnode_conn);
 	int (*logout_flashnode_sid) (struct iscsi_cls_session *cls_sess);
+	int (*get_host_stats) (struct Scsi_Host *shost, char *buf, int len);
 };
 
 /*