[bloaty] Don't close the pipe if it didn't get created

I was overaggressive on the closing :/

Change-Id: If0612c137a31bccee7b8123f161e9daa3322aab1
diff --git a/bloaty/bloaty.go b/bloaty/bloaty.go
index 152cbf6..3f0cbff 100644
--- a/bloaty/bloaty.go
+++ b/bloaty/bloaty.go
@@ -53,7 +53,6 @@
 	stdout, err := cmd.StdoutPipe()
 	if err != nil {
 		out <- bloatyOutput{err: fmt.Errorf("pipe: %s: %s", file, err)}
-		stdout.Close()
 		return
 	}