drm/bridge: imx: add driver for HDMI TX Parallel Audio Interface

drm/bridge: imx: add driver for HDMI TX Parallel Audio Interface

The HDMI TX Parallel Audio Interface (HTX_PAI) is a digital module that
acts as the bridge between the Audio Subsystem to the HDMI TX Controller.
This IP block is found in the HDMI subsystem of the i.MX8MP SoC.

Data received from the audio subsystem can have an arbitrary component
ordering. The HTX_PAI block has integrated muxing options to select which
sections of the 32-bit input data word will be mapped to each IEC60958
field. The HTX_PAI_FIELD_CTRL register contains mux selects to
individually select P,C,U,V,Data, and Preamble.

Use component helper so that imx8mp-hdmi-tx will be aggregate driver,
imx8mp-hdmi-pai will be component driver, then imx8mp-hdmi-pai can use
bind() ops to get the plat_data from imx8mp-hdmi-tx device.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Link: https://lore.kernel.org/r/20250923053001.2678596-6-shengjiu.wang@nxp.com