Initial code to support more than 32 cpus. The platform CPU mask
is updated from 32-bit mask to cpumask_t. Convert places that use
cpu_/cpus_ functions to use cpumask_* functions.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Patchwork: http://patchwork.linux-mips.org/patch/4464


Signed-off-by: John Crispin <blogic@openwrt.org>