fix: use uart source file in main

src/uart-transmit/main.c

@@ -2,6 +2,7 @@
 // All rights reserved
 
 #include <mdk.h>
+#include "esp32-c3-uart-interface.c"
 
 // On the ESP32C3 dev boards, the WS2812 LED is connected to GPIO 8
 static int ws_2812_pin = 8;
@@ -45,7 +46,6 @@ int main(void) {
   gpio_output(ws_2812_pin);
   init_uart();
   config_uart();
-  enable_uart_transmitter();
   uint8_t cycle = 0;
 
   for (;;) {