Remove more TODOs

- Some of them don't make sense anymore
- Some are deprecated and removed from the engine since a few versions
  already.

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

cli/command/system/info.go

@@ -176,21 +176,6 @@ func prettyPrintInfo(dockerCli command.Cli, info types.Info) error {
 		for _, lbl := range info.Labels {
 			fmt.Fprintln(dockerCli.Out(), " "+lbl)
 		}
-		// TODO: Engine labels with duplicate keys has been deprecated in 1.13 and will be error out
-		// after 3 release cycles (17.12). For now, a WARNING will be generated. The following will
-		// be removed eventually.
-		labelMap := map[string]string{}
-		for _, label := range info.Labels {
-			stringSlice := strings.SplitN(label, "=", 2)
-			if len(stringSlice) > 1 {
-				// If there is a conflict we will throw out a warning
-				if v, ok := labelMap[stringSlice[0]]; ok && v != stringSlice[1] {
-					fmt.Fprintln(dockerCli.Err(), "WARNING: labels with duplicate keys and conflicting values have been deprecated")
-					break
-				}
-				labelMap[stringSlice[0]] = stringSlice[1]
-			}
-		}
 	}
 
 	fmt.Fprintln(dockerCli.Out(), "Experimental:", info.ExperimentalBuild)