all: simplify switches (#17267)

* all: simplify switches

* silly mistake

eth/handler.go

@@ -744,8 +744,7 @@ func (pm *ProtocolManager) BroadcastTxs(txs types.Transactions) {
 func (pm *ProtocolManager) minedBroadcastLoop() {
 	// automatically stops if unsubscribe
 	for obj := range pm.minedBlockSub.Chan() {
-		switch ev := obj.Data.(type) {
-		case core.NewMinedBlockEvent:
+		if ev, ok := obj.Data.(core.NewMinedBlockEvent); ok {
 			pm.BroadcastBlock(ev.Block, true)  // First propagate block to peers
 			pm.BroadcastBlock(ev.Block, false) // Only then announce to the rest
 		}