This check (tlli != 0) was added in 2015 in
6d86628e5b, with the rationale below:
"""
To avoid dangling entries without a TLLI there (which cannnot be
retrieved anyway), the timer in the MS objects is not started after
all TBF have been detached, so that they get deleted immediately in
that case.
"""
The rationale makes sense, but through time the MS class was fixed to
return GSM_RESERVED_TMSI (0xFFFFFFFF) when no TMSI was available.
Hence, the check was wrong, and as a result, free() of MS containing
GSM_RESERVED_TMSI would be delayed over time by release timer.
Related: OS#6002
Change-Id: I7a694a30f8709c00af774846d7c4925cef253a71
Pau Espin
14379ef901