utils: fix ineffectual miner config flags (ethereum#21271)

Without use of global, these flags didn't actually modify
miner configuration, since we weren't grabbing from the
proper context scope, which should be global (vs. subcommand).

Signed-off-by: meows <b5c6@protonmail.com>

cmd/utils/flags.go

@@ -1402,10 +1402,10 @@ func setMiner(ctx *cli.Context, cfg *miner.Config) {
 		cfg.GasPrice = GlobalBig(ctx, MinerGasPriceFlag.Name)
 	}
 	if ctx.GlobalIsSet(MinerRecommitIntervalFlag.Name) {
-		cfg.Recommit = ctx.Duration(MinerRecommitIntervalFlag.Name)
+		cfg.Recommit = ctx.GlobalDuration(MinerRecommitIntervalFlag.Name)
 	}
 	if ctx.GlobalIsSet(MinerNoVerfiyFlag.Name) {
-		cfg.Noverify = ctx.Bool(MinerNoVerfiyFlag.Name)
+		cfg.Noverify = ctx.GlobalBool(MinerNoVerfiyFlag.Name)
 	}
 }