video: dw_hdmi: support SoC specific read/write ops

Some IPs like the meson VPU have a specific way to write to dw_hdmi
registers. Make it configurable.

Signed-off-by: Jorge Ramirez-Ortiz <jramirez@baylibre.com>
[added commit description]
Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
2 files changed