mips: octeon: Add misc cvmx-* header files

Import misc cvmx-helper header files from 2013 U-Boot. They will be used
by the later added drivers to support networking on the MIPS Octeon II /
III platforms.

Signed-off-by: Aaron Williams <awilliams@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>