Update RICH numbering scheme in PDPanels initialisation.
This MR updates the RICH PDPanel initialisation, keeping empty spaces in the used numbering scheme for non-existent elements (modules, PMTs).
Needed by: lhcb-conddb/DDDB!107 (merged), lhcb-conddb/SIMCOND!185 (merged) and backward compatible with older DB versions.
Edited by Bartosz Piotr Malecki