gbproxy: Move peer definitions to gb_proxy_peer.c

This patch moves the peer related definitions from gb_proxy.c to
gb_proxy_peer.c and adjusts the prefix of each global symbol to
gbproxy_:

Peer definitions (prefix adjusted to gbproxy_):
  peer_ctr_description -> gprs/gb_proxy_peer.c (static)
  peer_ctrg_desc -> gprs/gb_proxy_peer.c (static)
  *peer_by_* -> gprs/gb_proxy_peer.c
  gbproxy_peer_alloc -> gprs/gb_proxy_peer.c
  gbproxy_peer_free -> gprs/gb_proxy_peer.c
  gbprox_cleanup_peers -> gprs/gb_proxy_peer.c

Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy_vty.c b/openbsc/src/gprs/gb_proxy_vty.c
index b2f25a3..f1811c3 100644
--- a/openbsc/src/gprs/gb_proxy_vty.c
+++ b/openbsc/src/gprs/gb_proxy_vty.c
@@ -422,7 +422,7 @@
 	const uint16_t bvci = atoi(argv[1]);
 	int counter;
 
-	counter = gbprox_cleanup_peers(g_cfg, nsei, bvci);
+	counter = gbproxy_cleanup_peers(g_cfg, nsei, bvci);
 
 	if (counter == 0) {
 		vty_out(vty, "BVC not found%s", VTY_NEWLINE);
@@ -458,7 +458,7 @@
 
 	if (delete_bvc) {
 		if (!dry_run)
-			counter = gbprox_cleanup_peers(g_cfg, nsei, 0);
+			counter = gbproxy_cleanup_peers(g_cfg, nsei, 0);
 		else {
 			struct gbproxy_peer *peer;
 			counter = 0;
@@ -541,7 +541,7 @@
 		break;
 	}
 
-	peer = gbprox_peer_by_nsei(g_cfg, nsei);
+	peer = gbproxy_peer_by_nsei(g_cfg, nsei);
 	if (!peer) {
 		vty_out(vty, "Didn't find peer with NSEI %d%s",
 			nsei, VTY_NEWLINE);