Fix a couple of missing vendor targets in MM_VMS.pm.

Also, apparently uninstall became undeprecated at some point.
Trim return value of ExtUtiils::Liblist::Kid::_vms_ext.

The new tests look for an exact value, not an exact value modulo
whitespace, so we might as well clean this up here.
Fix t/Liblist_Kid.t for VMS.

_vms_ext always returns the value of the Perl shareable library
even if the inputs are empty or non-existent, so modify the
expectations of the test for VMS only.

We use a bunch of %Config variables that are always defined in the
real world, so define them to something in the test in order to
avoid a large number of uninitialized value warnings.
Remove VAXCCURSE from ExtUtils::Liblist::Kid::_vms_ext.

This library was for the ancient, pre-ANSI VAXC compiler.  Support
for that compiler was removed from Perl about fifteen years ago,
so let's reduce the clutter here.