Sometimes it isn't obvious which set of packages are removed from a
split package when the pkgbase matches also a subset of a pkgbase. This
can happen for example with bootstrapping packages, when the intention
is to just remove a partial part of the bootstrap pkgbase.

To make the intention more explicit, list all to be removed packages and
await for confirmation.

Component: pkgctl db remove
Signed-off-by: Levente Polyak <anthraxx@archlinux.org>