bcm6328, bcm6362 and bcm6368 targets are missing a key config symbol which
prevents the NAND from working.
Fixes: f6c02b014d ("bmips: 6.1: refresh config and add missing symbols")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
(cherry picked from commit 61da745817f28673b193d60bb4bc5b76dd215246)
65906202fc