DEFSTRUCT non bug

[Spiros Bousbouras]

This is regarding
https://gitlab.com/embeddable-common-lisp/ecl/issues/469 .I don't think that
the behaviour mentioned in there is a bug.  (defstruct foo a b c)  is top
level inside file  /tmp/foo.lisp  and CLHS says

    If a defstruct form appears as a top level form, the compiler must make the
    structure type name recognized as a valid type name in subsequent declarations
    (as for deftype) and make the structure slot readers known to setf.

So after  (compile-file "/tmp/foo.lisp")  it makes sense that FIND-CLASS would
know about  foo . SBCL behaves the same way.