Log current value of GOMAXPROCS

With `--runtime.gomaxprocs=0`, the GOMAXPROXS value will default to the
number of logical CPUs. In this case, it is more useful to log the
actual value than the value set by the user via the command-line.

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

node_exporter.go

@@ -183,7 +183,7 @@ func main() {
 		level.Warn(logger).Log("msg", "Node Exporter is running as root user. This exporter is designed to run as unprivileged user, root is not required.")
 	}
 	runtime.GOMAXPROCS(*maxProcs)
-	level.Debug(logger).Log("msg", "Go MAXPROCS", "procs", *maxProcs)
+	level.Debug(logger).Log("msg", "Go MAXPROCS", "procs", runtime.GOMAXPROCS(0))
 
 	http.Handle(*metricsPath, newHandler(!*disableExporterMetrics, *maxRequests, logger))
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {