Work around for an openocd build problem in the UK

[HamiltonIC]

If in the UK, the openocd package as installed by the Ibex demo system Dockerfile fails to build as it tries to fetch a couple of packages from the repo.or.cz git repository. This repository has blocked access from the UK due to the Online Safety Act 2023.

The work around is to add a couple of lines to the Dockerfile (the 'git submodule set-url' commands below) to change where the packages are fetched from:

RUN git clone https://github.com/openocd-org/openocd.git \
&& cd openocd \
&& git checkout v0.11.0 \
&& git submodule set-url tools/git2cl https://github.com/lobaro/git2cl.git \
&& git submodule set-url src/jtag/drivers/libjaylink https://gitlab.zapb.de/libjaylink/libjaylink \
&& ./bootstrap \
&& ./configure \
&& make \
&& mkdir -p /tools/openocd \
&& cp -r src /tools/openocd \
&& cd ..

This will only be required if you are in the UK, so I haven't created a branch for this. Just edit the Dockerfile with the above lines if affected.

[nbdd0121]

OpenOCD probably should just be updated openocd-org/openocd@94e7535