implement support for 3-digit MNC with leading zeros

Add 3-digit flags and use the new RAI and LAI API from libosmocore throughout
the code base to be able to handle an MNC < 100 that has three digits (leading
zeros).

Note that in gbproxy_test.ok, 0-0 changes to 000-000 instead of 000-00, because
the parsed ra buffer is 000000 which results in 000-000, while 00f000 would
result in 000-00. IOW this is expected.

Change-Id: I7437dfaa586689e2bef0d4be6537e5577a8f6c26
diff --git a/src/gprs/sgsn_vty.c b/src/gprs/sgsn_vty.c
index 9d1d86d..07d4293 100644
--- a/src/gprs/sgsn_vty.c
+++ b/src/gprs/sgsn_vty.c
@@ -484,11 +484,9 @@
 		pfx, mm->imsi, mm->imei, mm->p_tmsi, VTY_NEWLINE);
 	vty_out(vty, "%s  MSISDN: %s, TLLI: %08x%s HLR: %s",
 		pfx, mm->msisdn, mm->gb.tlli, mm->hlr, VTY_NEWLINE);
-	vty_out(vty, "%s  MM State: %s, Routeing Area: %u-%u-%u-%u, "
-		"Cell ID: %u%s", pfx,
-		get_value_string(gprs_mm_st_strs, mm->gmm_state),
-		mm->ra.mcc, mm->ra.mnc, mm->ra.lac, mm->ra.rac,
-		mm->gb.cell_id, VTY_NEWLINE);
+	vty_out(vty, "%s  MM State: %s, Routeing Area: %s, Cell ID: %u%s",
+		pfx, get_value_string(gprs_mm_st_strs, mm->gmm_state),
+		osmo_rai_name(&mm->ra), mm->gb.cell_id, VTY_NEWLINE);
 
 	vty_out_rate_ctr_group(vty, " ", mm->ctrg);