devel/libtar should install a shared library too

[Mikhail T.]

I tried building vlc-devel "with everything" -- including libtar.

I had to drop SVGALib because it is i386-only as per vendor, and
libtar because it is static library only as per our port. At least,
on amd64 one can not use a statc library to create a shared one.

Is there a good reason devel/libtar does not install a shared
version?

        -mi