arm64: dts: rockchip: fix pcie-refclk frequency on rk3588 tiger

The clock-generator of course only produces a 100MHz clock rate,
not 1GHz.

Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Reviewed-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Link: https://lore.kernel.org/r/20240423114635.2637310-1-heiko@sntech.de


Signed-off-by: Heiko Stuebner <heiko@sntech.de>