Add boot.scr snippet for handling the M4

- Check if m4enabled is set. If it's set to 1, attempt to load the
overlay. If that's successful, call the m4boot command to stuff the
binary into memory and kick the core.

Change-Id: Iad8d1ca8f1e04f08b5e747f0dc799f55466eb854
1 file changed
tree: e7ad2a2bbbd060b1d7874afe0eca5daa2a108971
  1. debian/