arm nomadik: rename board to nhk8815

This is an error in my side in the initial submission: nobody
calls it ""nmdk8815", it's "nomadik hardware kit", nhk8815, instead.

Signed-off-by: Alessandro Rubini <rubini@unipv.it>
Acked-by: Andrea Gallo <andrea.gallo@stericsson.com>
7 files changed