Eliminate some proto_tree_add_text from GSM dissectors (so now there are no dissectors with 100+ proto_tree_add_text calls).

Add tfs_allocated_by_receiver_sender to tfs.h because it seems "popular" enough.

Change-Id: I478461d9b951a2c3e3aec6aaf996d95ba2c0feee
Reviewed-on: https://code.wireshark.org/review/4708
Reviewed-by: Michael Mann <mmann78@netscape.net>
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>