[ros-diffs] [tkreuzer] 48366: [NTOS] The MADs from the bootloader should already know whether a page is in use or not. So it's not useful to scan the entire pagetable for mapped pfns to keep them out of the free list. Free descriptors should not be in use and if they are mapped, they should rather be unmapped than arbitrarily assuming a KSEG0 mapping later. This allows us to shuffle the order in which the PFN database is created: The MADs are parsed first, doing it in one loop with mapping the database in M