NLS: improve UTF8 -> UTF16 string conversion routine

The utf8s_to_utf16s conversion routine needs to be improved.  Unlike
its utf16s_to_utf8s sibling, it doesn't accept arguments specifying
the maximum length of the output buffer or the endianness of its
16-bit output.

This patch (as1501) adds the two missing arguments, and adjusts the
only two places in the kernel where the function is called.  A
follow-on patch will add a third caller that does utilize the new
capabilities.

The two conversion routines are still annoyingly inconsistent in the
way they handle invalid byte combinations.  But that's a subject for a
different patch.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
{
	struct inode *inode = dentry->d_inode;
	struct super_block *sb = dir->i_sb;
	struct fat_slot_info sinfo;
	int err;

	lock_super(sb);

	err = fat_dir_empty(inode);
	if (err)
		goto out;
	err = vfat_find(dir, &dentry->d_name, &sinfo);
	if (err)
		goto out;

	err = fat_remove_entries(dir, &sinfo);	/* and releases bh */
	if (err)
		goto out;
	drop_nlink(dir);

	clear_nlink(inode);
	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
	fat_detach(inode);
out:
	unlock_super(sb);

	return err;
}

static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
{
	struct inode *inode = dentry->d_inode;
	struct super_block *sb = dir->i_sb;
	struct fat_slot_info sinfo;
	int err;

	lock_super(sb);

	err = fat_dir_empty(inode);
	if (err)
		goto out;
	err = vfat_find(dir, &dentry->d_name, &sinfo);
	if (err)
		goto out;

	err = fat_remove_entries(dir, &sinfo);	/* and releases bh */
	if (err)
		goto out;
	drop_nlink(dir);

	clear_nlink(inode);
	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
	fat_detach(inode);
out:
	unlock_super(sb);

	return err;
}
