Removed emulation uart pin because can't be used currently.

Removed compilation warning error in timer.
Timer functions validated (Tone, Servo).

Signed-off-by: fpr <fabien.perroquin@wi6labs.com>

Author: fpr

variants/NUCLEO_F103RB/variant.h

@@ -135,10 +135,6 @@ uint32_t pinNametoPinNumber(PinName p);
 
 #define DEBUG_UART              ((USART_TypeDef *) USART2)
 
-// UART Emulation
-#define UART_EMUL_RX            PB13
-#define UART_EMUL_TX            PB14
-
 //Enable Firmata
 #define STM32 1