ppc4xx: respect 80-chars per line in ppc*.h files

After running checkstyle.pl on the three previous patches I noted that in
the *.h files there were a lot of long lines. This patch solves this problem.

Signed-off-by: Niklaus Giger <niklaus.giger@member.fsf.org>
Signed-off-by: Stefan Roese <sr@denx.de>