MT6572 UART进meta设定
MT6572 USB pin可以与uart1和uart2做share pin. MT6572这边会增加一个宏(CFG_USB_UART_SWITCH_PORT)来决定,默认是uart2.
#define CFG_UART_LOG (UART2)
#define CFG_UART_META (UART1)
#define CFG_USB_UART_SWITCH_PORT (UART2)
72的config =>透过USB PIN配置连接为Uart2，可以修改为Uart1，连接Meta 和抓log.
#define CFG_UART_LOG (UART2)
#define CFG_UART_META (UART1)
