Add display-controller to list of generic node names

The device-tree specification does not present a generic node name for
hardware compositors.  Several names are used, but 'display-controller'
is the most straight-forward name to describe such device.

Signed-off-by: Raphael Gallais-Pou <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

Author: GallaisPoutine

source/chapter2-devicetree-basics.rst

@@ -221,6 +221,7 @@ name should be one of the following choices:
    * crypto
    * disk
    * display
+   * display-controller
    * dma-controller
    * dsi
    * dsp