Updated sysctl usage for cpu

[johscheuer]

The determination of cpus fails on OSX and always return the default:

I0828 23:00:40.323360   98294 cmd.go:58] Executing local command:
I0828 23:00:40.323369   98294 cmd.go:59]   sysctl
I0828 23:00:40.323376   98294 cmd.go:61]   -n
I0828 23:00:40.323381   98294 cmd.go:61]   hw.ncpus
I0828 23:00:40.331770   98294 cmd.go:78] Error from execution: exit status 1
I0828 23:00:40.331822   98294 cmd.go:84] Errout:
sysctl: unknown oid 'hw.ncpus'

the command should be sysctl -n hw.ncpu but anyway this field is deprecated and shouldn't be used according to developer.apple. I assumed that we are checking the hardware cpus and replaced the command with sysctl -n hw.physicalcpu.

Tested on: Darwin Kernel Version 15.6.0

[csrwng]

@johscheuer thx for fixing this. To preserve the intent of the original code, I think we want hw.logicalcpu though.

[johscheuer]

@csrwng I changed it to hw.logicalcpu

[csrwng]

LGTM

[johscheuer]

@csrwng any action required from me?

[csrwng]

@johscheuer No, we are waiting for 1.3 to be released. When it is, then merges will be allowed in origin again.

[csrwng]

[merge]

[openshift-bot]

Evaluated for origin merge up to 4412719

[openshift-bot]

continuous-integration/openshift-jenkins/merge SUCCESS (https://ci.openshift.redhat.com/jenkins/job/test_pr_origin/9850/) (Image: devenv-rhel7_5161)