af_iucv: add sockopt() to enable/disable use of IPRM_DATA msgs

Provide the socket operations getsocktopt() and setsockopt() to enable/disable
sending of data in the parameter list of IUCV messages.
The patch sets respective flag only.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/iucv/af_iucv.h

@@ -73,8 +73,12 @@ struct iucv_sock {
 	struct sk_buff_head	backlog_skb_q;
 	struct sock_msg_q	message_q;
 	unsigned int		send_tag;
+	u8			flags;
 };
 
+/* iucv socket options (SOL_IUCV) */
+#define SO_IPRMDATA_MSG	0x0080		/* send/recv IPRM_DATA msgs */
+
 struct iucv_sock_list {
 	struct hlist_head head;
 	rwlock_t	  lock;