net.peer.name clarification for HTTP client semconv (#3276)

Fixes #3273

## Changes

Clarifies that if an HTTP client request is explicitly made to an IP
address, e.g. `http://x.x.x.x:8080`, then
`net.peer.name` SHOULD be the IP address `x.x.x.x`.

semantic_conventions/trace/http.yaml

@@ -72,7 +72,8 @@ groups:
             if it's sent in absolute-form
           - Host identifier of the `Host` header
 
-          SHOULD NOT be set if capturing it would require an extra DNS lookup.
+          If an HTTP client request is explicitly made to an IP address, e.g. `http://x.x.x.x:8080`, then
+          `net.peer.name` SHOULD be the IP address `x.x.x.x`. A DNS lookup SHOULD NOT be used.
       - ref: net.peer.port
         sampling_relevant: true
         requirement_level:

specification/trace/semantic_conventions/http.md

@@ -152,7 +152,8 @@ before any HTTP-redirects that may happen when executing the request.
   if it's sent in absolute-form
 - Host identifier of the `Host` header
 
-SHOULD NOT be set if capturing it would require an extra DNS lookup.
+If an HTTP client request is explicitly made to an IP address, e.g. `http://x.x.x.x:8080`, then
+`net.peer.name` SHOULD be the IP address `x.x.x.x`. A DNS lookup SHOULD NOT be used.
 
 **[4]:** When [request target](https://www.rfc-editor.org/rfc/rfc9110.html#target.resource) is absolute URI, `net.peer.name` MUST match URI port identifier, otherwise it MUST match `Host` header port identifier.