Fixes tendermint/tendermint#3522

* OriginalAddr -> SocketAddr

OriginalAddr records the originally dialed address for outbound peers,
rather than the peer's self reported address. For inbound peers, it was
nil. Here, we rename it to SocketAddr and for inbound peers, set it to
the RemoteAddr of the connection.

* use SocketAddr

Numerous places in the code call peer.NodeInfo().NetAddress().
However, this call to NetAddress() may perform a DNS lookup if the
reported NodeInfo.ListenAddr includes a name. Failure of this lookup
returns a nil address, which can lead to panics in the code.

Instead, call peer.SocketAddr() to return the static address of the
connection.

* remove nodeInfo.NetAddress()

Expose `transport.NetAddress()`, a static result determined
when the transport is created. Removing NetAddress() from the nodeInfo
prevents accidental DNS lookups.

* fixes from review

* linter

* fixes from review

p2p/node_info.go

@@ -23,14 +23,8 @@ func MaxNodeInfoSize() int {
 // NodeInfo exposes basic info of a node
 // and determines if we're compatible.
 type NodeInfo interface {
-	nodeInfoAddress
-	nodeInfoTransport
-}
-
-// nodeInfoAddress exposes just the core info of a node.
-type nodeInfoAddress interface {
 	ID() ID
-	NetAddress() *NetAddress
+	nodeInfoTransport
 }
 
 // nodeInfoTransport validates a nodeInfo and checks
@@ -221,7 +215,7 @@ func (info DefaultNodeInfo) NetAddress() *NetAddress {
 	if err != nil {
 		switch err.(type) {
 		case ErrNetAddressLookup:
-			// XXX If the peer provided a host name  and the lookup fails here
+			// XXX If the peer provided a host name and the lookup fails here
 			// we're out of luck.
 			// TODO: use a NetAddress in DefaultNodeInfo
 		default: