driveTxPriorityQueue(): check if message header format is supported
driveTxPriorityQueue(): check if message header format is supported

Change-Id: I17abf95f5e23236abccc50476cd59931580f5cd3

osmocom/osmo-trx,osmocom/osmo-trx,osmocom/osmo-trx,osmocom/osmo-trx