fc-target.h preprocessor symbols: introduce CONFIG_TARGET_LEO_RFFE Out of our currently existing supported targets, Leonardo and Tango use TI's classic Leonardo RFFE wiring. However, we would like to use the same quadband RFFE with the same classic wiring on our FreeCalypso Libre Dumbphone handset, and also on the planned development board that will serve as a stepping stone toward that goal. Therefore, we introduce the new CONFIG_TARGET_LEO_RFFE preprocessor symbol, and conditionalize on this symbol in tpudrv12.h, instead of a growing || of different targets.