docs: dt: writing-schema: Include the example schema in the doc build

The example-schema.yaml file serves as documentation, so let's include it
from writing-schema.rst.

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/20210325164713.1296407-4-robh@kernel.org
This commit is contained in:
Rob Herring 2021-03-25 10:47:08 -06:00
commit 9be21f7358