drm/i2c: move TDA998x driver under drivers/gpu/drm/bridge

drm/i2c: move TDA998x driver under drivers/gpu/drm/bridge

TDA998x is the HDMI bridge driver, incorporating drm_connector and
optional drm_encoder (created via the component bind API by the TICLDC
and HDLCD drivers). Thus it should be residing together with the other
DRM bridge drivers under drivers/gpu/drm/bridge/.

Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250113-drm-move-tda998x-v3-3-214e0682a5e4@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>