MIPS: kernel: cps-vec: Replace KSEG0 with CKSEG0

MIPS: kernel: cps-vec: Replace KSEG0 with CKSEG0

In preparation for 64-bit CPS support, we replace KSEG0 with CKSEG0
so 64-bit kernels can be supported.

Cc: <stable@vger.kernel.org> # 3.16+
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10590/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>