MINOR: config: relax the range checks on cpu-map

MINOR: config: relax the range checks on cpu-map

Emeric reports that when MAX_THREADS and/or MAX_PROCS are set to lower
values, referencing thread or process numbers higher than these limits
in cpu-map returns errors. This is annoying because these typically are
silent settings that are expected to be used only when set. Let's switch
back to LONGBITS for this limit.