makenemo does not create EXP00 for existing configs

Context

makenemo does not create EXP00 for existing configs

Analysis

EXP00 is created and filled by mk/Fmake_config.sh which is no more called if the config is already existing

Fix

• always call mk/Fmake_config.sh
• make sure mk/Fmake_config.sh is properly working when called on an existing config