Progress: * UM-2 [QEMU upstream maintainership] - investigated and fixed a bug in page-table-walk handling of debug accesses that was introduced by the FEAT_RME changes - that prompted me to look at a cleanup of some of the ptw code so that we consistently look at "which space is this walk for" and don't carry around a parallel boolean "secure/non-secure" that duplicates that information - found and fixed a few other ptw bugs along the way

-- PMM