arm64: dts: rockchip: Disable CDN DP on Pinebook Pro

The CDN DP needs a PHY and a extcon to work correctly. But no extcon is
provided by the device-tree, which leads to an error:
cdn-dp fec00000.dp: [drm:cdn_dp_probe [rockchipdrm]] *ERROR* missing extcon or phy
cdn-dp: probe of fec00000.dp failed with error -22

Disable the CDN DP to make graphic work on the Pinebook Pro.
Reported-by: Guillaume Gardet <guillaume.gardet@arm.com>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
Link: https://lore.kernel.org/r/20210715164101.11486-1-matthias.bgg@kernel.orgSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3399-pinebook-pro.dts

@@ -385,10 +385,6 @@ mains_charger: dc-charger {
 	};
 };
 
-&cdn_dp {
-	status = "okay";
-};
-
 &cpu_b0 {
 	cpu-supply = <&vdd_cpu_b>;
 };