Revert "discovery: add new option to toggle gossip rate limiting"

This reverts commit 13a2598ded.

discovery/gossiper.go

@@ -233,11 +233,6 @@ type Config struct {
 	// graph on connect.
 	IgnoreHistoricalFilters bool
 
-	// GossipUpdateThrottle if true, then the gossiper will throttle
-	// gossip updates to once per RebroadcastInterval for any keep-alive
-	// updates, and once per block for other types of updates.
-	GossipUpdateThrottle bool
-
 	// PinnedSyncers is a set of peers that will always transition to
 	// ActiveSync upon connection. These peers will never transition to
 	// PassiveSync.
@@ -1937,9 +1932,8 @@ func (d *AuthenticatedGossiper) processNetworkAnnouncement(
 
 		// If we have a previous version of the edge being updated,
 		// we'll want to rate limit its updates to prevent spam
-		// throughout the network if we're currently throttling such
-		// updates.
-		if d.cfg.GossipUpdateThrottle && nMsg.isRemote && edgeToUpdate != nil {
+		// throughout the network.
+		if nMsg.isRemote && edgeToUpdate != nil {
 			// If it's a keep-alive update, we'll only propagate one
 			// if it's been a day since the previous. This follows
 			// our own heuristic of sending keep-alive updates after