Setup-environment-internal: use getconf to determine the number of cpus

If /usr/bin/getconf exists use that, otherwise fallback to /proc/cpuinfo

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
Merge pull request #1 from koenkooi/patch-1

Setup-environment-internal: use getconf to determine the number of cpus