[OpenSIPS-Devel] [OpenSIPS/opensips] 68aaa2: [b2b_entitites] Fix crash on empty To display name.

[Bogdan Andrei IANCU]

  Branch: refs/heads/2.4
  Home:   https://github.com/OpenSIPS/opensips
  Commit: 68aaa20113dcbb12c3123108fbe2cbc11f5e7b82
      https://github.com/OpenSIPS/opensips/commit/68aaa20113dcbb12c3123108fbe2cbc11f5e7b82
  Author: Bogdan-Andrei Iancu <bogdan at opensips.org>
  Date:   2019-06-28 (Fri, 28 Jun 2019)

  Changed paths:
    M modules/b2b_entities/b2be_db.c

  Log Message:
  -----------
  [b2b_entitites] Fix crash on empty To display name.

As the To display name may be empty and the DB does not enforce a not NULL, better be ready to read a NULL.
This happens when using db_cachedb + cachedb_mongodb as backend
Closes #1606