Cleanup scripts debian / rpm packages

The following discussion from !11064 (merged) should be addressed:

• @abate started a discussion:

  if this is not needed we can remove it altogether instead of commenting out. Do you know exactly why this is a problem ? What is the error on AWS linux ? It sound wired that a check on undeclared variable will break the script. Maybe we really forgot to initialize some variables or catch some errors in the script ?