arm64: dts: rockchip: Add avdd HDMI supplies to RockPro64 board dtsi

arm64: dts: rockchip: Add avdd HDMI supplies to RockPro64 board dtsi

Add missing "avdd-0v9-supply" and "avdd-1v8-supply" properties to the "hdmi"
node in the Pine64 RockPro64 board dtsi file.  To achieve this, also add the
associated "vcca_0v9" regulator that produces the 0.9 V supply, [1][2] which
hasn't been defined previously in the board dtsi file.

This also eliminates the following warnings from the kernel log:

  dwhdmi-rockchip ff940000.hdmi: supply avdd-0v9 not found, using dummy regulator
  dwhdmi-rockchip ff940000.hdmi: supply avdd-1v8 not found, using dummy regulator

There are no functional changes to the way board works with these additions,
because the "vcc1v8_dvp" and "vcca_0v9" regulators are always enabled, [1][2]
but these additions improve the accuracy of hardware description.

These changes apply to the both supported hardware revisions of the Pine64
RockPro64, i.e. to the production-run revisions 2.0 and 2.1. [1][2]

[1] https://files.pine64.org/doc/rockpro64/rockpro64_v21-SCH.pdf
[2] https://files.pine64.org/doc/rockpro64/rockpro64_v20-SCH.pdf

Fixes: e4f3fb490967 ("arm64: dts: rockchip: add initial dts support for Rockpro64")
Cc: stable@vger.kernel.org
Suggested-by: Diederik de Haas <didi.debian@cknow.org>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Tested-by: Diederik de Haas <didi.debian@cknow.org>
Link: https://lore.kernel.org/r/df3d7e8fe74ed5e727e085b18c395260537bb5ac.1740941097.git.dsimic@manjaro.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>