MAINTAINERS: add Calxeda Highbank ARM platform

Adding maintainer for arch/arm/mach-highbank/

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
1 file changed