Add proper copyright notices in Atmel boards Makefiles

The Makefiles for the AT91CAP9/AT91SAM9 boards have an incomplete
copyright notice. This patch adds the missing pieces.

Signed-off-by: Stelian Pop <stelian@popies.net>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>