gbproxy: Use the term 'link' instead of 'tlli'

Currently in many places where 'tlli' (Temporary Logical Link
Identifier) within identifiers is used, the logical link itself is
meant instead. For instance, the tlli_info contain information about
an LLC logical link including up to four individual TLLI.

To avoid confusion between these concepts, this patch replaces all
'tlli_info' by 'link_info' and a few 'tlli' by 'link'.

Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy_peer.c b/openbsc/src/gprs/gb_proxy_peer.c
index 335b46f..8f90665 100644
--- a/openbsc/src/gprs/gb_proxy_peer.c
+++ b/openbsc/src/gprs/gb_proxy_peer.c
@@ -172,7 +172,7 @@
 {
 	llist_del(&peer->list);
 
-	gbproxy_delete_tlli_infos(peer);
+	gbproxy_delete_link_infos(peer);
 
 	rate_ctr_group_free(peer->ctrg);
 	peer->ctrg = NULL;