[Toybox] ls -l / doesn't work on pie.

[Rob Landley]

I installed terminal on my new phone and the first command I ran was "ls -l"
which said:

  ls: .: Permission denied

Which seems to be the same problem as 527045debecb but my question is are you
intentionally trying to prevent readdir() on / (so the command line is kinda
useless because you don't know what directories you can descend into) or do I
just need to add O_PATH to the open in dirtree() and allow stat() to fail in
some circumstances?

(How I tell it's a directory if stat failed is an interesting question, but I
guess in that case I can just _try_ to descend and see if I get a different error?)

What exactly did this selinux addition defend against, anyway?

Rob