FILESEXTRAPATHS_prepend := “${THISDIR}/linux-toradex_5.4-2.3.x:${THISDIR}/linux-toradex_5.4-2.3.x/mx8”
You are missing the terminal colon above which then later mangles your second path with our path where those scc files should be found. It should look as follows instead:
FILESEXTRAPATHS_prepend := "${THISDIR}/linux-toradex_5.4-2.3.x:${THISDIR}/linux-toradex_5.4-2.3.x/mx8:"