bundle.bbclass: extend do_bundle[file-checksums]

Rerun do_bundle task when RAUC_CERT_FILE or RAUC_KEY_FILE files have
been changed on the disk.

Signed-off-by: Grygorii Tertychnyi <grembeter@gmail.com>

classes-recipe/bundle.bbclass

@@ -448,6 +448,7 @@ do_bundle() {
 }
 do_bundle[dirs] = "${B}"
 do_bundle[cleandirs] = "${B}"
+do_bundle[file-checksums] += "${RAUC_CERT_FILE}:True ${RAUC_KEY_FILE}:True"
 
 addtask bundle after do_configure