tbf: Always call set_tlli/confirm_tlli in update_ms

Currently the m_tlli member in GprsMs is set by the constructor,
circumventing the TLLI confirmation mechanism.

This commit replaces the get_or_create_ms() method by a create_ms()
method which takes the TLLI and the direction (UL or DL) as
parameters to select either set_tlli() or confirm_tlli(). The MS
object is instantiated with TLLI = 0, and therefore GprsMs::tlli() is
extended to return the DL TLLI if both of the other TLLI are not set.

Note that create_ms() will not check whether an MS object with a
matching TLLI is already stored in the list, so it should only be
called after a corresponding get_ms() in general.

Sponsored-by: On-Waves ehf
8 files changed