If I enable api-documentation and build a sdk: WARNING: core-image-sato-1.0-r0 do_populate_sdk: Intentionally failing postinstall scriptlets of ['kmod-doc'] to defer them to first boot is deprecated. Please place them into pkg_postinst_ontarget_${PN} (). If deferring to first boot wasn't the intent, then scriptlet failure may mean an issue in the recipe, or a regression elsewhere. This isn't an intentionally failing postinst as it doesn't 'exit 1' anywhere, so the postinst doesn't work properly in the context of a SDK.
I tested this locally with current master and it seems the issues were resolved with the various recent postinst changes and other fixes.