dt-bindings: display: bridge: tc358762: Document reset-gpios

This chip has one reset GPIO input, document it. The reset GPIO
is optional as it is sometimes not connected on some hardware.

Signed-off-by: Marek Vasut <marex@denx.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230530192805.648646-1-marex@denx.de

Documentation/devicetree/bindings/display/bridge/toshiba,tc358762.yaml

@@ -21,6 +21,9 @@ properties:
     maxItems: 1
     description: virtual channel number of a DSI peripheral
 
+  reset-gpios:
+    maxItems: 1
+
   vddc-supply:
     description: Regulator for 1.2V internal core power.