Fix fs tests to avoid deleting /usr to certain systems.

cmd/fs-v1-helpers_test.go

@@ -18,7 +18,6 @@ package cmd
 
 import (
 	"bytes"
-	"runtime"
 	"testing"
 )
 
@@ -396,10 +395,4 @@ func TestFSRemoves(t *testing.T) {
 	if err = fsRemoveAll("my-obj-del-0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001"); err != errFileNameTooLong {
 		t.Fatal(err)
 	}
-
-	if runtime.GOOS != "windows" {
-		if err = fsRemoveAll("/usr"); err != errVolumeAccessDenied {
-			t.Fatal(err)
-		}
-	}
 }