MIPS: Give Octeon+ CPUs their own cputype.

This allows us to treat them differently at runtime.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/951/
Patchwork: http://patchwork.linux-mips.org/patch/987/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>