Fix FE numbering in pixel module design for for run 3 endcap modules.
For run3 the pixel endcap modules with even phi index have mirrored front-end numbering i.e. the top row starts at 15 rather than 0.
The front-end numbers provided by the module design are only used by the Acts based chain. The non-acts chain still uses the PixelReadoutManager.
Closes ATLIDTRKCP-755