HPCC-9535 Rationalize Roxie topology info

Non-default multicast addresses were not working

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #4565 from richardkchapman/roxie-multicast

HPCC-9535 Rationalize Roxie topology info

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>