[media] em28xx: Fix some Terratec entries (H5 and XS)

As reported by  Andreas Oberritter <obi@linuxtv.org>, changeset
33ba28ee did the wrong thing.

Fix it to properly reflect the entries for Terratec H5 revs 1 and 2,
and restore Terratec XS entry.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>