video: console: Remove reference to CONFIG_8xx

CONFIG_8xx is deprecated and should soon be removed in favor
of CONFIG_PPC_8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>