sgsn: Extract the hlr Number into the mm context

Include the hlr-Number of the subscriber in the CDR. This is useful
for debugging and understanding which equipment was used during the
test. In contrast to the MSISDN the '+' is emitted as the number
must be in international format already.
diff --git a/openbsc/src/gprs/sgsn_vty.c b/openbsc/src/gprs/sgsn_vty.c
index 8b6e3ec..b7023ad 100644
--- a/openbsc/src/gprs/sgsn_vty.c
+++ b/openbsc/src/gprs/sgsn_vty.c
@@ -315,8 +315,8 @@
 {
 	vty_out(vty, "%sMM Context for IMSI %s, IMEI %s, P-TMSI %08x%s",
 		pfx, mm->imsi, mm->imei, mm->p_tmsi, VTY_NEWLINE);
-	vty_out(vty, "%s  MSISDN: %s, TLLI: %08x%s", pfx, mm->msisdn,
-		mm->tlli, VTY_NEWLINE);
+	vty_out(vty, "%s  MSISDN: %s, TLLI: %08x%s HLR: %s",
+		pfx, mm->msisdn, mm->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->mm_state),