cmd: gomtree no arguments

my tar_stream_tar_time PR accidentally put the functionality
for when gomtree has no arguments inside an unreachable block.

Signed-off-by: Stephen Chung <schung@redhat.com>

cmd/gomtree/main.go

@@ -223,6 +223,7 @@ func main() {
 					fmt.Printf("%s missing\n", missingpath)
 				}
 			}
+		}
 	} else {
 		log.Println("neither validating or creating a manifest. Please provide additional arguments")
 		isErr = true
@@ -230,7 +231,6 @@ func main() {
 		return
 	}
 }
-}
 
 func splitKeywordsArg(str string) []string {
 	return strings.Fields(strings.Replace(str, ",", " ", -1))