etc/kamailio.cfg: add return to root blocks

- make it more explicit for returned code

etc/kamailio.cfg

@@ -567,6 +567,8 @@ request_route {
 
 	# user location service
 	route(LOCATION);
+
+	return;
 }
 
 # Wrapper for relaying requests
@@ -1002,6 +1004,7 @@ route[TOVOICEMAIL] {
 branch_route[MANAGE_BRANCH] {
 	xdbg("new branch [$T_branch_idx] to $ru\n");
 	route(NATMANAGE);
+	return;
 }
 
 # Manage incoming replies
@@ -1010,6 +1013,7 @@ reply_route {
 		xlog("Malformed SIP response from $si:$sp\n");
 		drop;
 	}
+	return;
 }
 
 # Manage incoming replies in transaction context
@@ -1018,6 +1022,7 @@ onreply_route[MANAGE_REPLY] {
 	if(status=~"[12][0-9][0-9]") {
 		route(NATMANAGE);
 	}
+	return;
 }
 
 # Manage failure routing cases
@@ -1051,4 +1056,5 @@ failure_route[MANAGE_FAILURE] {
 		exit;
 	}
 #!endif
+	return;
 }