Fix some uglyness

Attached is a patch that fixes some global ugliness. The dependencies are a bit iffy, so you need a make clean after applying this. This fix needs to be in place before you decode multiple carriers. I would like to suggest that tetra-rx.c be changed so that it can receive multiplexed streams of input. Byte values of 0 / 1 will be the primary stream, but other values can be used to encode the multiplexed streams. The easiest method is to use the high order bits of the input as a "stream id", and dynamically create new state structs as they appear in the stream. Does this sound like a decent solution ? f