Preliminary support for DU product builds [2/2]

Credit/Thanks to CM

Change-Id: I4e1e1662a4d530c32ccc0fe44b5b7ad39464d21f
Fix custom OUT_DIR

If OUT_DIR is set to anything but out in your working directory
then squisher and opticharger will fail.  This fixes that
issue

Change-Id: I29ebeb8ce30f9f14dbbf18362d15dc45cb775660