As of today we assumed that "machine_desc->init_per_cpu" calls
are only usable on SMP systems when we want to run some piece of
code on early boot for each and every core, I guess assumption was
we have "machine_desc->init_early" for single-core cases where
the one and only master core can do all the things.
But it turned out for platforms which might be both UP and SMP it
might be benificial to use "init_per_cpu" for both UP and SMP cases
with which we achieve 2 things simultaneously:
1) Exactly the same one code will be used for UP&SMP for
things required to be done on each an every core regardless if it's
a master and the only core in UP system or any other slave core in SMP
setup.
1) There will be no "ifdef CONFIG_SMP" around "init_per_cpu".