mount.cifs: on 2nd try mount.cifs must also uppercase "orig_dev"

Recent kernels now ignore "unc=..." mount option. mount.cifs, when
getting errno=ENXIO, retries the mount with uppercased hostname,
sharename and prefixpath in the "unc=..." mount option, which is ignored
now in the kernel. Used e.g. during OS/2 mounts, which fail now.

Also uppercase the now used "orig_dev" parameter.

Signed-off-by: Guenter Kukkukk <kukks@samba.org>
autoconf: set version to 6.4

Signed-off-by: Jeff Layton <jlayton@samba.org>