Security: Invalid access when calling fake without 'make' or 'build'.

Security: Invalid access when calling fake without 'make' or 'build'.

This is caused by the F_data_not return result not being processed in some of the fl_fss functions.

Additional changes:
- Make the return status constant.
- The status is being returned regardless in some cases so remove the effectively redundant lines of code.
- Combined the additional if condition blocks together.