util: Add docker to automate creation of documentation

Build with:
 docker build --force-rm -t "doc.flashrom.org" \
	      "$PWD/util/docker/flashrom.org/"

Generate HTML files:
 mkdir -p "$PWD/doc/_build/"
 docker run -it --rm \
            --user "$(id -u):$(id -g)" \
            -v "$PWD/:/data-in/:ro" \
            -v "$PWD/doc/_build/:/data-out/" \
            doc.flashrom.org

Live web server:
 docker run -it --rm \
            --net=host -v "$PWD/:/data-in/:ro" \
            doc.flashrom.org livehtml

Change-Id: I889fa5f98e2fd6ef896ba4bb30aa5d985ff82622
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/75344
Reviewed-by: Anastasia Klimchuk <aklm@chromium.org>
Tested-by: Anastasia Klimchuk <aklm@chromium.org>

util/docker/flashrom.org/README.md

@@ -0,0 +1,32 @@
+# doc.coreboot.org
+ Docker container for generating and developing documentation for doc.coreboot.org
+
+**NOTE**: All paths are from the base of the coreboot git repo.
+
+### Build
+
+```sh
+  docker build --force-rm -t "doc.flashrom.org" "$PWD/util/docker/flashrom.org/"
+```
+
+### Generating production HTML
+
+```sh
+# To ensure the output directory is given the correct permissions, make sure to
+# created it before running docker the first time.
+mkdir -p "$PWD/doc/_build/"
+
+docker run -it --rm \
+           --user "$(id -u):$(id -g)" \
+           -v "$PWD/:/data-in/:ro" \
+           -v "$PWD/doc/_build/:/data-out/" \
+           doc.flashrom.org
+```
+
+### live reloaded with web server
+On the host machine, open a browser to the address http://0.0.0.0:8000
+```sh
+docker run -it --rm \
+           --net=host -v "$PWD/:/data-in/:ro" \
+           doc.flashrom.org livehtml
+```