drm/bridge: Add bindings for TI THS8134

This adds device tree bindings for the Texas Instruments
THS8134, THS8134A and THS8134B VGA DACs by extending and
renaming the existing bindings for THS8135.

These DACs are used for the VGA outputs on the ARM reference
designs such as Integrator, Versatile and RealView.

Cc: devicetree@vger.kernel.org
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: NRob Herring <robh@kernel.org>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180112074854.9560-1-linus.walleij@linaro.org

Documentation/devicetree/bindings/display/bridge/ti,ths8135.txt → Documentation/devicetree/bindings/display/bridge/ti,ths813x.txt

-THS8135 Video DAC
------------------
+THS8134 and THS8135 Video DAC
+-----------------------------
 
-This is the binding for Texas Instruments THS8135 Video DAC bridge.
+This is the binding for Texas Instruments THS8134, THS8134A, THS8134B and
+THS8135 Video DAC bridges.
 
 Required properties:
 
-- compatible: Must be "ti,ths8135"
+- compatible: Must be one of
+  "ti,ths8134"
+  "ti,ths8134a," "ti,ths8134"
+  "ti,ths8134b", "ti,ths8134"
+  "ti,ths8135"
 
 Required nodes: