MIPS: Octeon: Set appropriate endianness in L2C registers

Signed-off-by: Paul Martin <paul.martin@codethink.co.uk>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9629/


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