Log Message:
Fix handling of tcl and tk versions: don't demand exact version when
the version we have doesn't include the teeny version number.

Possibly we should arrange to pass that in and require it exactly; I'm
not sure exactly what the compatibility semantics of version numbers
are supposed to be in tcl-land; but it's definitely wrong the way it
has been.

Fixes PR 50244 wherein tkined fails to run.