Potential bug in trx_if.c

Hey all, I've been working on getting the Range Networks RAD1 working with OsmoBTS. I *think* I've found a bug in trx_if.c. Basically, tsc checks the bsic variable and bsic checks the tsc variable. It *may* be intentional but I doubt that and I wanted to note it before I moved on. Patch is attached. Thanks!