If a SDK needs to run a postinst intercept, be it in the target sysroot or the nativesdk sysroot, it will fail.

This is simply because we don't set INTERCEPT_DIR or run the intercepts, because those are actions that rootfs.py takes, whereas the sdk (sdk.py) uses the package managers directly.

We should probably move the intercept logic somewhere common like package_manager.py, so the sdk code can reuse it.

poky-contrib:ross/interceptargh has a vague attempt at copy/paste which doesn't work (conflating host and target intercepts) which may be interesting as an example of what not to do.

Reproducer:

CORE_IMAGE_EXTRA_INSTALL_append = " glib-networking"
$ bitbake core-image-minimal -c populate_sdk