dt-bindings: drm/bridge: ti-sn65dsi83: Add vcc supply bindings

Add a VCC regulator which needs to be enabled before the EN pin is
released.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211213133626.2498056-4-alexander.stein@ew.tq-group.com