drm/meson: venc: add ENCL encoder setup for MIPI-DSI output

This adds supports for the ENCL encoder connected to a MIPI-DSI transceiver on the
Amlogic AXG, G12A, G12B & SM1 SoCs.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Nicolas Belin <nbelin@baylibre.com>
Tested-by: Nicolas Belin <nbelin@baylibre.com> # on Khadas VIM3 + TS050 Panel
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230512-amlogic-v6-4-upstream-dsi-ccf-vim3-v5-10-56eb7a4d5b8e@linaro.org