hfsplus: fix getxattr return value

We need to support -EOPNOTSUPP for attributes that are not supported to
match other filesystems and allow userspace to detect if Posix ACLs
are supported or not.  setxattr already gets this right.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>

fs/hfsplus/ioctl.c

@@ -192,7 +192,7 @@ ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
 		} else
 			res = size ? -ERANGE : 4;
 	} else
-		res = -ENODATA;
+		res = -EOPNOTSUPP;
 out:
 	if (size)
 		hfs_find_exit(&fd);