cmd/geth: allow configuring metrics HTTP server on separate endpoint (#21290)

Exposing /debug/metrics and /debug/metrics/prometheus was dependent
on --pprof, which also exposes other HTTP APIs. This change makes it possible
to run the metrics server on an independent endpoint without enabling pprof.

cmd/geth/main.go

@@ -199,6 +199,8 @@ var (
 	metricsFlags = []cli.Flag{
 		utils.MetricsEnabledFlag,
 		utils.MetricsEnabledExpensiveFlag,
+		utils.MetricsHTTPFlag,
+		utils.MetricsPortFlag,
 		utils.MetricsEnableInfluxDBFlag,
 		utils.MetricsInfluxDBEndpointFlag,
 		utils.MetricsInfluxDBDatabaseFlag,