install: Rename install -> install to-disk, peer with to-filesystem

[cgwalters]

install: Rename install -> install to-disk, peer with to-filesystem

Take the current install verb and change it to be
bootc install to-disk, and then install-to-filesystem becomes
bootc install to-filesystem - they are obvious peers.

The main motivation here is that in the end many use cases will
want nontrivial filesystem customization, and while I like having
a fully opinionated builtin flow to write to a target disk,
we should really think of to-filesystem as a fully equal peer
of to-disk.

Signed-off-by: Colin Walters [email protected]

---

install-to-disk: Verify target is a block device

I saw someone get confused and think bootc install could work
on a filesystem.

Signed-off-by: Colin Walters [email protected]

---

install-to-filesystem: Verify target is a dir+mountpoint

Similarly to previous patch for install to-disk, verify
that the target is a directory and that it's a mountpoint (we
can't sanely support installing to a subdirectory of a filesystem).

Signed-off-by: Colin Walters [email protected]

---

[sallyom]

LGTM

[jerpeter1]

Possible (more simple? ) alternative: Keep bootc install, and add an error if bootc install targets a non-device, non-mountpoint.

[cgwalters]

Possible (more simple? ) alternative: Keep bootc install, and add an error if bootc install targets a non-device, non-mountpoint.

There's a bit more rationale to why to make install a standalone verb in
osbuild/bootc-image-builder#18 (comment)

[rhatdan]

Should we keep bootc install to disk and
bootc install --file-system

If we expect one to happen more often then the other?

[cgwalters]

Should we keep bootc install to disk and bootc install --file-system

That doesn't feel very different from the status quo though...and more importantly the reason there's a separate verb (i.e. CLI command) today is that the two paths have a few mutually-incompatible extra arguments (e.g. install has --filesystem but obviously can't do that with to-filesystem; it's already made), and to-filesystem has --root-mount-spec which doesn't make sense when targeting a blockdev.

[rhatdan]

LGTM