arm64: dts: rockchip: Enable HDMI PHY clk provider on rk3576

arm64: dts: rockchip: Enable HDMI PHY clk provider on rk3576

As with the RK3588 SoC, the HDMI PHY PLL on RK3576 can be used as a more
accurate pixel clock source for VOP2, which is actually mandatory to
ensure proper support for display modes handling.

Add the missing #clock-cells property to allow using the clock provider
functionality of HDMI PHY.

Fixes: ad0ea230ab2a ("arm64: dts: rockchip: Add hdmi for rk3576")
Cc: stable@vger.kernel.org
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Tested-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Link: https://lore.kernel.org/r/20250612-rk3576-hdmitx-fix-v1-2-4b11007d8675@collabora.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>