eth: move eth.Config to a common package (ethereum#22205)

This moves the eth config definition into a separate package, eth/ethconfig. 
Packages eth and les can now import this common package instead of
importing eth from les, reducing dependencies.

Co-authored-by: Felix Lange <fjl@twurst.com>

cmd/faucet/faucet.go

@@ -47,8 +47,8 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/eth"
 	"github.com/ethereum/go-ethereum/eth/downloader"
+	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/ethclient"
 	"github.com/ethereum/go-ethereum/ethstats"
 	"github.com/ethereum/go-ethereum/les"
@@ -247,7 +247,7 @@ func newFaucet(genesis *core.Genesis, port int, enodes []*enode.Node, network ui
 	}
 
 	// Assemble the Ethereum light client protocol
-	cfg := eth.DefaultConfig
+	cfg := ethconfig.Defaults
 	cfg.SyncMode = downloader.LightSync
 	cfg.NetworkId = network
 	cfg.Genesis = genesis

cmd/geth/config.go

@@ -27,7 +27,7 @@ import (
 	"gopkg.in/urfave/cli.v1"
 
 	"github.com/ethereum/go-ethereum/cmd/utils"
-	"github.com/ethereum/go-ethereum/eth"
+	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/internal/ethapi"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/metrics"
@@ -85,7 +85,7 @@ type whisperDeprecatedConfig struct {
 }
 
 type gethConfig struct {
-	Eth      eth.Config
+	Eth      ethconfig.Config
 	Shh      whisperDeprecatedConfig
 	Node     node.Config
 	Ethstats ethstatsConfig
@@ -121,7 +121,7 @@ func defaultNodeConfig() node.Config {
 func makeConfigNode(ctx *cli.Context) (*node.Node, gethConfig) {
 	// Load defaults.
 	cfg := gethConfig{
-		Eth:     eth.DefaultConfig,
+		Eth:     ethconfig.Defaults,
 		Node:    defaultNodeConfig(),
 		Metrics: metrics.DefaultConfig,
 	}

cmd/utils/cmd.go

@@ -33,7 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/eth"
+	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/internal/debug"
 	"github.com/ethereum/go-ethereum/log"
@@ -75,7 +75,7 @@ func StartNode(ctx *cli.Context, stack *node.Node) {
 		signal.Notify(sigc, syscall.SIGINT, syscall.SIGTERM)
 		defer signal.Stop(sigc)
 
-		minFreeDiskSpace := eth.DefaultConfig.TrieDirtyCache
+		minFreeDiskSpace := ethconfig.Defaults.TrieDirtyCache
 		if ctx.GlobalIsSet(MinFreeDiskSpaceFlag.Name) {
 			minFreeDiskSpace = ctx.GlobalInt(MinFreeDiskSpaceFlag.Name)
 		} else if ctx.GlobalIsSet(CacheFlag.Name) || ctx.GlobalIsSet(CacheGCFlag.Name) {