cosmetic: remove obsolete ROLE_BSC

It's leftover from the time when gsm_data_shared.* was actually shared
with OsmoBTS. Nowadays ROLE_BSC is always defined so we can just drop it
entirely and make working with gsm_data_shared.h slightly easier.

Change-Id: I34fc9ee5955c14bbbde68d5499cf2acfd329afbc
3 files changed