uart-to-dmx: support DMX1 through 3

#include "driver/stdout.h"

#include "driver/stdin.h"

#include "driver/uptime.h"

#include "driver/dmx.h"

#if defined(CONFIG_meta_driver_dmx1)

#include "driver/dmx1.h"

#define dmx dmx1

#elif defined(CONFIG_meta_driver_dmx2)

#include "driver/dmx2.h"

#define dmx dmx2

#elif defined(CONFIG_meta_driver_dmx3)

#include "driver/dmx3.h"

#define dmx dmx3

#else

#error "No DMX driver found"

#endif

#include "driver/timer.h"

volatile unsigned char timer_done = 0;