remove broken/unneeded code

Author: benwaffle

cores/arduino/stm32/uart.c

@@ -557,26 +557,18 @@ size_t uart_write(serial_t *obj, uint8_t data, uint16_t size)
   */
 void uart_debug_init(void)
 {
-  void *periph = DEBUG_UART;
-  if (periph != NP) {
-    serial_debug.pin_rx = pinmap_pin(periph, PinMap_UART_RX);
+  if (DEBUG_UART != NP) {
+    serial_debug.pin_rx = pinmap_pin(DEBUG_UART, PinMap_UART_RX);
 #if defined(DEBUG_PINNAME_TX)
     serial_debug.pin_tx = DEBUG_PINNAME_TX;
 #else
-    serial_debug.pin_tx = pinmap_pin(periph, PinMap_UART_TX);
+    serial_debug.pin_tx = pinmap_pin(DEBUG_UART, PinMap_UART_TX);
 #endif
     serial_debug.baudrate = DEBUG_UART_BAUDRATE;
     serial_debug.parity = UART_PARITY_NONE;
     serial_debug.databits = UART_WORDLENGTH_8B;
     serial_debug.stopbits = UART_STOPBITS_1;
 
-    if (periph == USART1)
-      serial_debug.irq = USART1_IRQn;
-    else if (periph == USART2)
-      serial_debug.irq = USART2_IRQn;
-    else if (periph == USART3)
-      serial_debug.irq = USART3_IRQn;
-
     uart_init(&serial_debug);
   }
 }