arm64: dts: amlogic: add power domain to hdmitx

arm64: dts: amlogic: add power domain to hdmitx

HDMI Tx needs HDMI Tx memory power domain turned on. This power domain is
handled under the VPU power domain.

The HDMI Tx currently works because it is enabling the PD by directly
poking the power controller register. It is should not do that but properly
use the power domain controller.

Fix this by adding the power domain to HDMI Tx.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20240625145017.1003346-3-jbrunet@baylibre.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>