ARM: dts: sun8i: r40: Remove fallback compatible for TCON TV

A83T and R40 TCON TV are very similar. However, R40 TCON TV is wired
differently, which makes it incompatible with A83T TCON TV.

Because of that, remove fallback A83T TCON TV compatible.

Fixes: 05a43a26 ("ARM: dts: sun8i: r40: Add HDMI pipeline")

Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>