arm64: dts: rockchip: Assign RT5616 MCLK rate on rk3588-friendlyelec-cm3588

arm64: dts: rockchip: Assign RT5616 MCLK rate on rk3588-friendlyelec-cm3588

The Realtek RT5616 audio codec on the FriendlyElec CM3588 module fails
to probe correctly due to the missing clock properties. This results
in distorted analogue audio output.

Assign MCLK to 12.288 MHz, which allows the codec to advertise most of
the standard sample rates per other RK3588 devices.

Fixes: e23819cf273c ("arm64: dts: rockchip: Add FriendlyElec CM3588 NAS board")
Signed-off-by: Tom Vincent <linux@tlvince.com>
Link: https://lore.kernel.org/r/20250417081753.644950-1-linux@tlvince.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>