In some cases GsmArfcn itself is not enough. It case of L1CTL
and GSMTAP, it needs to be equipped with a band discriminator:
- DCS / PCS (as the numbers may overlap),
- Downlink / Uplink (not yet there).
Let's rename this record and move it to GSM_Types. Also, add
send / receive tamplates, so we can add new fields later.
Change-Id: I7a63f03bbd15a06caafb786122dc12991d115771