vlr_sgs: start lu expiration timer on sgs eps detach

When the subscriber is detached from SGs services (but not from 2g
services). Then the subscriber essentially becomes a regular 2g
subscriber, which means thet the lu expiration timer needs to be
started.

Change-Id: If95c63706dc1c5a537f7cd1b6481252427cbf234
Related: OS#3614
1 file changed