lcCT: use the correct index for checking the second byte

(Not that it will make any difference, as the checking of these
high bits looks like an excess of precaution.)

This fixes issue #134.

Reported-by: Rafał Mikrut

Signed-off-by: Benno Schulenberg <bensberg@telfort.nl>
6 jobs for misindex in 5 minutes and 9 seconds (queued for 1 second)