Your could check platform files of BCM943362WCD4 and/or BCM9WCDPLUS114 as reference!
Both already configure two UART port!
WICED_UART_2 has not been connected to the FTDI chip. As a result, you will have to modify the hardware as well as the platform files.
BTW, we just want a regular UART ... not a terminal one with serial to USB or vice-versa conversion.