Deprecate unmaintained processes

The four processes were not extended and maintained for some time already and are marked as deprecated for the OGS-6.5.3 and will be removed in OGS-6.5.5.

The new cmake option OGS_BUILD_DEPRECATED_PROCESSES is available and is set to OFF by default.

1. Feature description was added to the changelog
2. Tests covering your feature were added?
3. Any new feature or behaviour change was documented?