UART3 RX and TX pins are now moved to support uart download capability
on the platform. Old pins are now GPIOs routed to expansion ports.
All original boards should either have been returned for modifications
or already modified for the required change and maintaining
compatibility for older boards are no longer needed.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>