code: avoid golang-lint error for TxLookupLimit

eth/ethconfig/config.go

@@ -110,7 +110,7 @@ type Config struct {
 	PipeCommit          bool
 	RangeLimit          bool
 
-	// Deprecated: use 'TransactionHistory' instead.
+	// Deprecated, use 'TransactionHistory' instead.
 	TxLookupLimit      uint64 `toml:",omitempty"` // The maximum number of blocks from head whose tx indices are reserved.
 	TransactionHistory uint64 `toml:",omitempty"` // The maximum number of blocks from head whose tx indices are reserved.
 	StateHistory       uint64 `toml:",omitempty"` // The maximum number of blocks from head whose state histories are reserved.