libostree/deploy: create composefs image even if maybe

Currently, we only create a composefs image if the enablement level is
`true`. But ISTM there's no reason we shouldn't lower the threshold to
`maybe` instead.

This makes it slightly less awkward to ratchet in composefs. Without
this, it's hard to have new nodes use composefs while still allowing
old nodes with ancient libostree to upgrade to the same image (without
composefs).

src/libostree/ostree-sysroot-deploy.c

@@ -667,7 +667,7 @@ checkout_deployment_tree (OstreeSysroot *sysroot, OstreeRepo *repo, OstreeDeploy
   g_debug ("composefs enabled by config: %d repo: %d", composefs_enabled, repo->composefs_wanted);
   if (repo->composefs_wanted == OT_TRISTATE_YES)
     composefs_enabled = repo->composefs_wanted;
-  if (composefs_enabled == OT_TRISTATE_YES)
+  if (composefs_enabled != OT_TRISTATE_NO)
     {
       composefs_start_time = g_get_monotonic_time ();
       // TODO: Clean up our mess around composefs/fsverity...we have duplication

tests/test-admin-deploy-composefs.sh

@@ -30,7 +30,7 @@ cd osdata
 mkdir -p usr/lib/ostree
 cat > usr/lib/ostree/prepare-root.conf << 'EOF'
 [composefs]
-enabled=true
+enabled=maybe
 EOF
 ${CMD_PREFIX} ostree --repo=${test_tmpdir}/testos-repo commit --add-metadata-string version=1.composefs -b testos/buildmain/x86_64-runtime
 cd -