more space for vlr_number and sgsn_number

To be able to handle our 20 chars long IPA tags, enlarge the vlr_number and
sgsn_number storage in struct hlr_subscriber.

Technically, osmo-hlr should be able to store any type of Global Title, blob of
arbitrary size. For our purposes, 32 is enough for now.

Related: OS#2796
Change-Id: I0121f1c4dbda3a076d780a3834281b21dab85493
diff --git a/src/db.h b/src/db.h
index 92fdac4..956b5ed 100644
--- a/src/db.h
+++ b/src/db.h
@@ -69,8 +69,8 @@
 	char		imsi[GSM23003_IMSI_MAX_DIGITS+1];
 	char		msisdn[GT_MAX_DIGITS+1];
 	/* imeisv? */
-	char		vlr_number[GT_MAX_DIGITS+1];
-	char		sgsn_number[GT_MAX_DIGITS+1];
+	char		vlr_number[32];
+	char		sgsn_number[32];
 	char		sgsn_address[GT_MAX_DIGITS+1];
 	/* ggsn number + address */
 	/* gmlc number */