nitb: Add a missing NULL check for searching the subscriber

 "subscriber " SUBSCR_TYPES " ID sms pending-send

could fail with an invalid ID/IMSI for the subscriber.

Fixes: Coverity CID 1040715
1 file changed
tree: a441be7415f456b4d09fdb81406cc493bbd433ff
  1. debian/
  2. hlrsync/
  3. linux-kernel/
  4. openbsc/
  5. wireshark/
  6. README