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
1 file changed