ARM: dts: rockchip: Remove unnecessary setting of UART0 SCLK rate on veyron

Some veyron devices have a Bluetooth controller connected on UART0.
The UART needs to operate at a high speed, however setting the clock
rate at initialization has no practical effect. During initialization
user space adjusts the UART baudrate multiple times, which ends up
changing the SCLK rate. After a successful initiatalization the clk
is running at the desired speed (48MHz).

Remove the unnecessary clock rate configuration from the DT.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>