faq: add entry about Fedora Bootc and FCOS

As Fedora Bootc gains more visibility, there are recurring questions
about its relationship to FCOS. Let's add an entry in the FAQ for this.

modules/ROOT/pages/faq.adoc

@@ -23,6 +23,28 @@ variety of containerized use cases, RHEL CoreOS provides a
 focused OS for OpenShift, released and life-cycled in tandem
 with the platform.
 
+== How does Fedora CoreOS relate to Fedora Bootc?
+
+https://docs.fedoraproject.org/en-US/bootc/[Fedora Bootc] is
+a Fedora project aimed at building Fedora and CentOS-based
+https://containers.github.io/bootable/[bootable containers]. The goal is to
+eventually have Fedora CoreOS build on top of Fedora Bootc both literally and in
+the broader sense of being part of the same ecosystem. The roadmap for this can
+be found https://github.com/coreos/fedora-coreos-tracker/issues/1726[on GitHub].
+
+Fedora CoreOS adds
+https://docs.fedoraproject.org/en-US/fedora-coreos/update-streams/[a stream model],
+platform-specific integration and disk images, provisioning via Ignition, and
+more tooling around automatic updates. The goal is also to have Fedora CoreOS
+integrate more strongly with the Kubernetes ecosystem.
+
+If you find yourself needing to heavily customize Fedora CoreOS beyond what
+https://docs.fedoraproject.org/en-US/fedora-coreos/os-extensions/[OS extensions]
+provide, it might make more sense to instead build on top of Fedora Bootc
+directly. It will eventually be possible to layer Ignition and e.g. Zincati
+on top if desired. These tools are intended to be used generically and are not
+strictly tied to Fedora CoreOS.
+
 == What are the communication channels around Fedora CoreOS?
 
 We have the following new communication channels around Fedora CoreOS: