classes/populate_sdk_ext: exclude initramfs images from locked signatures
Tasks for image recipes cannot be locked - there's nothing to restore
from shared state to cover them and as a result, if you had "live" in
IMAGE_FSTYPES the build would fail with "taskhash mismatch" errors for
do_rootfs and do_image_complete for the initramfs image recipe, since it
had to try to run those. We should probably catch that issue earlier in
the build and produce a proper error, but for now at least exclude these
signatures from the locked-sigs.inc file so that extensible SDK
installers built when IMAGE_FSTYPES includes "live". (It turned out we
already had code to find other image tasks in the task list in order to
generate the list of install targets.)
Follow-up fix for [YOCTO #9826].
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
