arch: smp: Allow for number of cpus to be determined at runtime

Introduce a Kconfig (MP_MAX_NUM_CPUS) and an api arch_num_cpus() to
allow for systems that might determine the number of CPUs available to
Zephyr at runtime.

CONFIG_MP_MAX_NUM_CPUS is intented to be use for any array initialization
and such that need to occur at build time.  For most systems
arch_num_cpus() will just report the value of CONFIG_MP_MAX_NUM_CPUS.

The intent is to phase out CONFIG_NP_NUM_CPUS.

Signed-off-by: Kumar Gala <kumar.gala@intel.com>
8 files changed