Enable transaction matching using callid and cseq values instead of via md5 value.

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#### Description <!-- Describe your changes in detail -->

Hello,

We had an issue with kamailio that the generated tm p_cell->md5 was not sent out in Via "branch=" parameter. Instead, other value was sent. Thus when comparing the replies Via "branch=" md5 value back to p_cell->md5, the transactions mismatched and dialogs were not setup. This happened for the most of the transactions/dialogs.

We could not really figure out why the above was happening. Because this was an isolated system, we decided to do this workaround using callid and cseq matching for transactions, and it helped. Now most of the dialogs are setup.

Let me know what you think, if other had this problem and if this PR helps.

Thank you, Stefan You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/2868

-- Commit Summary --

* <a href="https://github.com/kamailio/kamailio/pull/2868/commits/ab42c71fa814a9d2f3d85f10c1519ffd0fdf3369">tm: Add callid_cseq_matching param</a>

-- File Changes --

M src/modules/tm/config.c (3) M src/modules/tm/config.h (1) M src/modules/tm/doc/params.xml (23) M src/modules/tm/t_lookup.c (20) M src/modules/tm/tm.c (1)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/2868.patch https://github.com/kamailio/kamailio/pull/2868.diff