This makes us savestate the NAND using the same APIs the guest uses
instead of directly touching the host files. This solves several
problems:
* If the user loaded a malicious savestate, it could use path traversal
to overwrite arbitrary files on the host file system. (Reported by
MrSynAckster.)
* Metadata (UID, GID, attribute, modes) wasn't being savestated.
* NAND redirects weren't handled, except for NAND redirects at the root
of where the savestate was being done. (This only possibly matters if
TASing a Riivolution patch. The root of the savestate is at /tmp when
not TASing, and the only case where we do a NAND redirect is inside
/title if requested by a Riivolution patch.)
JosJuice
d35fe1b78b