bug#63757: 29.0.91 order of package paths changed: random old versions of packages in load-path

[Stefan Monnier]

> - I'm not sure the change of `package-disabled-p` =>
>   `package-built-in-p` is right: it makes the code obey the comment, but
>   I don't think we want to prefer built-in packages.

Scratch that, I see I was misremembering how `package-built-in-p` works,
this part of the change might be OK, actually.


        Stefan