Changes

trau2rtp HR: update to TW-TS-002 version 1.2.0

osmo_trau2rtp() in HRv1 mode emits either RFC 5993 or TW-TS-002
format, depending on whether or not the latter extended format is
enabled.  TW-TS-002 can represent BFIs and invalid SID frames,
in addition to good speech and valid SID in common with RFC 5993.

TW-TS-002 spec has recently been updated to version 1.2.0:

https://www.freecalypso.org/specs/tw-ts-002-v010200.txt

The principal difference is the way invalid SID frames are
represented: in version 1.1.0 all payload bits were stripped
in the case of invalid SID; version 1.2.0 allows these payload
bits to be preserved if they exist.  Section 5.4 in the new spec
version provides the detailed rationale for this change.

Change osmo_trau2rtp() operating on HR frames in TW-TS-002 mode
to emit invalid SID frames in the "verbose" form of TW-TS-002
version 1.2.0.

Compatibility considerations: there is no currently released or
deployed software that accepts TW-TS-002 version 1.1.0 but not
version 1.2.0.  More specifically:

* osmo_rtp2trau() in TRAU-UL/TFO output mode accepts invalid SID
  in both short and long forms since first implementation;

* Themyscira libgsmhr1, the library that accepts TW-TS-002 RTP input
  for either full speech decoding or TFO transform, has not yet
  reached its first release.  The current code in Hg implements
  TW-TS-002 version 1.2.0, thus the library will support both short
  and long forms of invalid SID upon its upcoming first release.

Change-Id: I497ad7b1f0f7229dc9a50cd3cc318e3dc1394171