rockchip: serial: Kconfig: add select SYS_NS16550 to config ROCKCHIP_SERIAL

The Rockchip serial driver depends on an enabled NS16550 driver,
so add select SYS_NS16550 to config ROCKCHIP_SERIAL.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
1 file changed