Don't discard all results if an unexpected reply comes back.

ssdp/ssdp.go

@@ -56,7 +56,7 @@ func SSDPRawSearch(httpu *httpu.HTTPUClient, searchTarget string, maxWaitSeconds
 		}
 		if st := response.Header.Get("ST"); st != searchTarget {
 			log.Printf("ssdp: got unexpected search target result %q", st)
-			return nil, nil
+			continue
 		}
 		location, err := response.Location()
 		if err != nil {