Guard macro unification/cleanup

lib/c/2006/labcomm2006.h

lib/c/2006/labcomm2006_default_error_handler.h

lib/c/2006/labcomm2006_default_memory.h

lib/c/2006/labcomm2006_default_scheduler.h

lib/c/2006/labcomm2006_dynamic_buffer_writer.h

lib/c/2006/labcomm2006_error.h

lib/c/2006/labcomm2006_fd_reader.h

lib/c/2006/labcomm2006_fd_writer.h

lib/c/2006/labcomm2006_ioctl.h

lib/c/2006/labcomm2006_private.h

lib/c/2006/labcomm2006_pthread_scheduler.h

lib/c/2006/labcomm2006_scheduler.h

lib/c/2006/labcomm2006_scheduler_private.h

lib/c/2006/labcomm_compat_vxworks.h

lib/c/2014/labcomm.h

lib/c/2014/labcomm_default_error_handler.h

lib/c/2014/labcomm_default_memory.h

lib/c/2014/labcomm_default_scheduler.h

lib/c/2014/labcomm_dynamic_buffer_writer.h

lib/c/2014/labcomm_error.h