Make inversion.el obsolete (Bug#46841)

Make inversion.el obsolete (Bug#46841)

* lisp/cedet/inversion.el:
* test/lisp/cedet/inversion-tests.el: Move from here...
* lisp/obsolete/inversion.el:
* test/lisp/obsolete/inversion-tests.el: ...to here.

* lisp/cedet/cedet.el (cedet-version): Make obsolete.
* lisp/cedet/cedet-cscope.el (cedet-cscope-version-check):
* lisp/cedet/cedet-global.el (cedet-gnu-global-version-check):
* lisp/cedet/cedet-idutils.el (cedet-idutils-version-check):
* lisp/cedet/ede/make.el (ede-make-check-version): Use 'version<'
instead of 'inversion-check-version'.
* lisp/cedet/semantic/db-file.el (semanticdb-load-database): Don't
use 'inversion-test'.
* lisp/cedet/semantic/ede-grammar.el
(ede-proj-makefile-insert-variables): Don't add inversion to
loadpath.
* lisp/speedbar.el: Remove stale comment.