'RELENG_5_3_0_RELEASE'.

This commit was manufactured to restore the state of the 5.3-RELEASE image.

FAT32 filesystems to be mounted, subject to some fairly serious limitations.

This works by extending the internal pseudo-inode-numbers generated from
the file's starting cluster number to 64-bits, then creating a table
mapping these into arbitrary 32-bit inode numbers, which can fit in
struct dirent's d_fileno and struct vattr's va_fileid fields. The mappings
do not persist across unmounts or reboots, so it's not possible to export
these filesystems through NFS. The mapping table may grow to be rather
large, and may grow large enough to exhaust kernel memory on filesystems
with millions of files.

Don't enable this option unless you understand the consequences.

- CD9660_ICONV, NTFS_ICONV and MSDOSFS_ICONV kernel options
(with corresponding modules).
- kiconv(3) for loadable charset conversion tables support.

Submitted by:	Ryuichiro Imura <imura@ryu16.org>

Not objected to by:	-current

- msdos.ko -> msdosfs.ko
- mount_msdos(8) -> mount_msdosfs(8)
- "msdos" -> "msdosfs" compatibility glue in mount(8)

it with vfsload("msdos").

(The proper fix would be to rename the `msdos' file system to
`msdosfs' in VFS_SET(), and mount_msdos(8) to mount_msdosfs(8).
But that would break too many existing fstab(5) setups, and
would require a lot of unnecessary documentation and code
msdos -> msdosfs changes.)

Noticed by:	markm

- msdos.ko renamed to msdosfs.ko
- /usr/include/msdosfs moved to /usr/include/fs/msdosfs

encoding the relative path.