eth/downloader: SetBlocksIdle is not used (#17962)

__
 <(o )___
  ( ._> /
   `---'

eth/downloader/peer.go

@@ -229,13 +229,6 @@ func (p *peerConnection) SetHeadersIdle(delivered int) {
 	p.setIdle(p.headerStarted, delivered, &p.headerThroughput, &p.headerIdle)
 }
 
-// SetBlocksIdle sets the peer to idle, allowing it to execute new block retrieval
-// requests. Its estimated block retrieval throughput is updated with that measured
-// just now.
-func (p *peerConnection) SetBlocksIdle(delivered int) {
-	p.setIdle(p.blockStarted, delivered, &p.blockThroughput, &p.blockIdle)
-}
-
 // SetBodiesIdle sets the peer to idle, allowing it to execute block body retrieval
 // requests. Its estimated body retrieval throughput is updated with that measured
 // just now.