x86: move and enhance debug printk for nr_cpu_ids etc.

Impact: cleanup, better debugging

This has proven useful in debugging, *before* we try to use
for_each_possible_cpu().  It also now shows nr_cpumask_bits.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>