libcommon: socket: extend make_sock() prototype

This patch extends the make_sock() prototype so you can fully set
the fields priv_nr and data of the bsc_fd structure.

This is the first step to get rid of the internal make_sock()
implementation that ipaccess-proxy uses.

This patch includes a minor cleanup to pass INADDR_ANY instead
of zero, if you do not want to bind the socket to one specific
address.
diff --git a/openbsc/src/osmo-bsc_nat/bsc_ussd.c b/openbsc/src/osmo-bsc_nat/bsc_ussd.c
index 0dd0d87..50c50ed 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_ussd.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_ussd.c
@@ -251,7 +251,7 @@
 
 	nat->ussd_listen.data = nat;
 	return make_sock(&nat->ussd_listen, IPPROTO_TCP,
-			 ntohl(addr.s_addr), 5001, ussd_listen_cb);
+			 ntohl(addr.s_addr), 5001, 0, ussd_listen_cb, NULL);
 }
 
 static int forward_ussd(struct sccp_connections *con, const struct ussd_request *req,