and adjust callers appropriately. cn_nameptr isn't NUL-terminated
for non-leaf components, so it's incorrect to assume it is always
NUL-terminated.
This fixes previous utf8-ization changes to not panic for cases
like 'echo */*/*.ps' in case the intermediate path components
are not in cache (yet).
into UTF-8, rather than filtering them to ISO-8859-1 subset
provide vfs.cd9660.utf8_joliet sysctl to switch to the former
iso-8859-1-only handling, default is to UTF-8 encode