eth, les, light: enforce CHT checkpoints on fast-sync too

eth/sync.go

@@ -188,14 +188,12 @@ func (pm *ProtocolManager) synchronise(peer *peer) {
 		atomic.StoreUint32(&pm.fastSync, 1)
 		mode = downloader.FastSync
 	}
-
 	if mode == downloader.FastSync {
 		// Make sure the peer's total difficulty we are synchronizing is higher.
 		if pm.blockchain.GetTdByHash(pm.blockchain.CurrentFastBlock().Hash()).Cmp(pTd) >= 0 {
 			return
 		}
 	}
-
 	// Run the sync cycle, and disable fast sync if we've went past the pivot block
 	if err := pm.downloader.Synchronise(peer.id, pHead, pTd, mode); err != nil {
 		return