build: update to latest lightning-onion version

go.mod

@@ -5,7 +5,6 @@ require (
 	github.com/NebulousLabs/fastrand v0.0.0-20180208210444-3cf7173006a0 // indirect
 	github.com/NebulousLabs/go-upnp v0.0.0-20180202185039-29b680b06c82
 	github.com/Yawning/aez v0.0.0-20180114000226-4dad034d9db2
-	github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da // indirect
 	github.com/btcsuite/btcd v0.0.0-20190426011420-63f50db2f70a
 	github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f
 	github.com/btcsuite/btcutil v0.0.0-20190425235716-9e5f4b9a998d
@@ -29,7 +28,7 @@ require (
 	github.com/juju/version v0.0.0-20180108022336-b64dbd566305 // indirect
 	github.com/kkdai/bstream v0.0.0-20181106074824-b3251f7901ec
 	github.com/lightninglabs/neutrino v0.0.0-20190426010803-a655679fe131
-	github.com/lightningnetwork/lightning-onion v0.0.0-20180605012408-ac4d9da8f1d6
+	github.com/lightningnetwork/lightning-onion v0.0.0-20190430041606-751fb4dd8b72
 	github.com/lightningnetwork/lnd/queue v1.0.1
 	github.com/lightningnetwork/lnd/ticker v1.0.0
 	github.com/ltcsuite/ltcd v0.0.0-20190101042124-f37f8bf35796