fix(plat/marvell/a3720/uart): configure UART after TX FIFO reset

If TX FIFO is not empty, do not touch UART settings and let UART HW
transmit remaining bytes from TX FIFO. New UART settings are then set
only after TX FIFO is reset.

Signed-off-by: Pali Rohár <pali@kernel.org>
Change-Id: I2976c0a4fbb841d3a79d42ef67c06e70174afc3b
1 file changed