Update origin and copyright information in arch-at91sam9 header files

When doing the AT91CAP9/AT91SAM9 port, a number of header files were
copied from the Linux kernel sources. This patch explicitly specifies
this origin for all the copied headers, and for those missing copyright
information, adds it.

Additionaly, the header file 'at91sam926x_mc.h' has been superceeded
in the latest kernel sources by 'at91sam9_smc.h'.

The copyright information has been confirmed by the AT91 Linux kernel
maintainer, Andrew Victor <avictor.za@gmail.com>.

Signed-off-by: Stelian Pop <stelian@popies.net>