drm/bridge: adv7533: Initial support for ADV7533

ADV7533 is a DSI to HDMI encoder chip. It is a derivative of ADV7511,
with additional blocks to translate input DSI data to parallel RGB
data. Besides the ADV7511 I2C register map, it has additional registers
that require to be configured to activate the DSI Rx block.

Create a new config that enables ADV7533 support. Use DT compatible
strings to populate the ADV7533 type enum. Add minimal register
configurations belonging to the DSI/CEC register map. Keep the ADV7533
code in a separate file.

Originally worked on by Lars-Peter Clausen <lars@metafoo.de>

Signed-off-by: Archit Taneja <architt@codeaurora.org>