Increase OCMBFW PNOR partition to 1164kb
Increase OCMBFW PNOR partition to 1164kb

We recently got confirmation from MSCC that the maximum explorer
flash image size is 1026k.  Adding 4kb for hostboot header +
4kb for secureboot header brings this to 1034kb.  Adding ECC
brings the total max size to 1164kb.  Only need this in Axone
layout for now.

open-power/pnor