gprs_gsup_client*: remove the gprs_ prefix

Make sure everything is named gsup_client_ / GSUP_CLIENT_.

Rename static gsup_client_send() to client_send() to avoid clash with public
gprs_gsup_client_send() being renamed to gsup_client_send().

This is in preparation for moving gsup to libcommon, which is in turn
preparation for libvlr. libvlr and osmo-sgsn will use the same GSUP client
code. A number of patches will follow up on this, also for the the OAP client.

Related: OS#1592
Change-Id: I57433973b1c4f6cc1e12e7b1c96b5f719f418b51
diff --git a/openbsc/src/gprs/gprs_subscriber.c b/openbsc/src/gprs/gprs_subscriber.c
index 658ce04..100fd91 100644
--- a/openbsc/src/gprs/gprs_subscriber.c
+++ b/openbsc/src/gprs/gprs_subscriber.c
@@ -45,7 +45,7 @@
 
 extern void *tall_bsc_ctx;
 
-static int gsup_read_cb(struct gprs_gsup_client *gsupc, struct msgb *msg);
+static int gsup_read_cb(struct gsup_client *gsupc, struct msgb *msg);
 
 /* TODO: Some functions are specific to the SGSN, but this file is more general
  * (it has gprs_* name). Either move these functions elsewhere, split them and
@@ -62,7 +62,7 @@
 
 	addr_str = inet_ntoa(sgi->cfg.gsup_server_addr.sin_addr);
 
-	sgi->gsup_client = gprs_gsup_client_create(
+	sgi->gsup_client = gsup_client_create(
 		addr_str, sgi->cfg.gsup_server_port,
 		&gsup_read_cb,
 		&sgi->cfg.oap);
@@ -73,7 +73,7 @@
 	return 1;
 }
 
-static int gsup_read_cb(struct gprs_gsup_client *gsupc, struct msgb *msg)
+static int gsup_read_cb(struct gsup_client *gsupc, struct msgb *msg)
 {
 	int rc;
 
@@ -161,7 +161,7 @@
 static int gprs_subscr_tx_gsup_message(struct gsm_subscriber *subscr,
 				       struct osmo_gsup_message *gsup_msg)
 {
-	struct msgb *msg = gprs_gsup_msgb_alloc();
+	struct msgb *msg = gsup_client_msgb_alloc();
 
 	if (strlen(gsup_msg->imsi) == 0 && subscr)
 		strncpy(gsup_msg->imsi, subscr->imsi, sizeof(gsup_msg->imsi) - 1);
@@ -176,7 +176,7 @@
 		return -ENOTSUP;
 	}
 
-	return gprs_gsup_client_send(sgsn->gsup_client, msg);
+	return gsup_client_send(sgsn->gsup_client, msg);
 }
 
 static int gprs_subscr_tx_gsup_error_reply(struct gsm_subscriber *subscr,