destdir: 'make package' inconsistency

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

I've not so recently noticed that 'make package' with destdir has
different behaviour than without destdir.

Currently (without destdir), make package does
        make && make install && create binary package
With destdir, it does
        make && create binary package
but doesn't install it.

I think that 'make package' behaviour shouldn't change just because of
the destdir toggle. I suggest adding a separate target for
        make && create binary package
and let 'make package' do
        make && create binary package && make install
to match what it does without destdir.

Comments?
Suggestions for a name for that new target?
 Thomas