ild_codgen.py: handle empty top-level maps
ild_codgen.py: handle empty top-level maps

Change-Id: If857cf29a0b8cc2ebaf10fe59f767d3f6cfc98b8
(cherry picked from commit d7d95091e4bbe3826a27965a9e8d6139ecd7563a)

intelxed/xed,intelxed/xed,intelxed/xed,intelxed/xed