Generate PIC for protobuf sources if BUILD_SHARED_LIBS==1
Generate PIC for protobuf sources if BUILD_SHARED_LIBS==1

lightstep/lightstep-tracer-cpp,lightstep/lightstep-tracer-cpp,lightstep/lightstep-tracer-cpp,lightstep/lightstep-tracer-cpp,lightstep/lightstep-tracer-cpp