* trxcon/l1sched: transmit dummy speech blocks with inverted CRC3
* trxcon/l1sched: do not craft artificial BFI frames on TCH
* trxcon/l1sched: simplify and unify prim_dequeue_tchf()
* trxcon/l1sched: peoperly prioritize FACCH/H over TCH
* trxcon/l1sched: rework dequeueing of Tx prims
* trxcon/l1sched: remove unused vars in l1sched_lchan_amr_prim_is_valid()
* trxcon/l1sched: fix handling of UL FACCH on TCH/A[FH]S
* trx_toolkit/data_msg.py: legacy flag is only for version 0x00
* trx_toolkit/data_msg.py: introduce header coding version 0x01
* trx_toolkit/data_msg.py: implement header version coding