LLC: Fixup element order in LLC-XID

When the LLC-XID request is constructed the order of the elements
in the TLV structure is reversed. This is in theory not a problem,
but differs from what we know from our practical experience. This
commit fixes the problem.

Change-Id: I1d71c947350d3c5a85ff36b71c1b8f036071d162
diff --git a/openbsc/src/gprs/gprs_llc.c b/openbsc/src/gprs/gprs_llc.c
index e5a80e5..0215029 100644
--- a/openbsc/src/gprs/gprs_llc.c
+++ b/openbsc/src/gprs/gprs_llc.c
@@ -77,9 +77,9 @@
 	xid_n201i.data_len = 2;
 
 	/* Add locally managed XID Fields */
-	llist_add(&xid_n201i.list, &xid_fields);
-	llist_add(&xid_n201u.list, &xid_fields);
 	llist_add(&xid_version.list, &xid_fields);
+	llist_add(&xid_n201u.list, &xid_fields);
+	llist_add(&xid_n201i.list, &xid_fields);
 
 	/* Append layer 3 XID field (if present) */
 	if (l3_xid_field) {