Update Zipkin remoteEndpoint preferences (open-telemetry#3087)

* Update Zipkin remoteEndpoint preferences

Do not reference semantic conventions that have been removed.

* net.peer.port -> net.sock.peer.port

specification/trace/sdk_exporters/zipkin.md

@@ -95,16 +95,16 @@ always available. The following table lists the possible attributes for
 |---|---|---|
 |1|peer.service|[OpenTelemetry adopted attribute for remote service.](../semantic_conventions/span-general.md#general-remote-service-attributes)|
 |2|net.peer.name|[OpenTelemetry adopted attribute for remote hostname, or similar.](../semantic_conventions/span-general.md#general-network-connection-attributes)|
-|3|net.peer.ip & net.peer.port|[OpenTelemetry adopted attribute for remote address of the peer.](../semantic_conventions/span-general.md#general-network-connection-attributes)|
-|4|peer.hostname|Remote hostname defined in OpenTracing specification.|
-|5|peer.address|Remote address defined in OpenTracing specification.|
-|6|http.host|Commonly used HTTP host header attribute for Http Spans.|
+|3|net.sock.peer.name|[OpenTelemetry adopted attribute for remote socket hostname of the peer.](../semantic_conventions/span-general.md#general-network-connection-attributes)|
+|4|net.sock.peer.addr & net.sock.peer.port|[OpenTelemetry adopted attribute for remote socket address of the peer.](../semantic_conventions/span-general.md#general-network-connection-attributes)|
+|5|peer.hostname|Remote hostname defined in OpenTracing specification.|
+|6|peer.address|Remote address defined in OpenTracing specification.|
 |7|db.name|Commonly used database name attribute for DB Spans.|
 
 * Ranking should control the selection order. For example, `net.peer.name` (Rank
-  2) should be selected before `http.host` (Rank 6).
-* `net.peer.ip` can be used by itself as `remoteEndpoint` but should be combined
-  with `net.peer.port` if it is also present.
+  2) should be selected before `peer.address` (Rank 6).
+* `net.sock.peer.name` and `net.sock.peer.addr` can be used by themselves as `remoteEndpoint` but should be combined
+  with `net.sock.peer.port` if it is also present.
 
 #### Zipkin -> OTLP