dt-bindings: display: bridge: ldb: Document nxp, enable-termination-resistor

Document the optional nxp,enable-termination-resistor property for the
i.MX LVDS display bridge.

This boolean property indicates that the built-in 100 Ohm termination
resistor on the LVDS output is enabled. It is controlled via the HS_EN
bit in the LVDS_CTRL register. Enabling the resistor can improve LVDS
signal quality and may prevent visual artifacts on some boards, but
increases the power consumption.

Signed-off-by: Fabio Estevam <festevam@nabladev.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Link: https://lore.kernel.org/r/20260120231930.2782444-1-festevam@gmail.com

Documentation/devicetree/bindings/display/bridge/fsl,ldb.yaml

@@ -35,6 +35,15 @@ properties:
       - const: ldb
       - const: lvds
 
+  nxp,enable-termination-resistor:
+    type: boolean
+    description:
+      Indicates that the built-in 100 Ohm termination resistor on the LVDS
+      output is enabled. This property is optional and controlled via the
+      HS_EN bit in the LVDS_CTRL register. Enabling it can improve signal
+      quality and prevent visual artifacts on some boards, but increases
+      power consumption.
+
   ports:
     $ref: /schemas/graph.yaml#/properties/ports
 
@@ -74,6 +83,15 @@ allOf:
           properties:
             port@2: false
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: fsl,imx6sx-ldb
+    then:
+      properties:
+        nxp,enable-termination-resistor: false
+
 additionalProperties: false
 
 examples: