website: Add v22.0.0.0 doxygen Change-Id: I12b728519d2657dd296019f9138a8cf990393965 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5-website/+/60513 Tested-by: Bobby Bruce <bbruce@ucdavis.edu> Maintainer: Bobby Bruce <bbruce@ucdavis.edu> Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>