AppArmor: Cleanup make file to remove cruft and make it easier to read

Cleanups based on comments from Sam Ravnborg,

* remove references to the currently unused af_names.h
* add rlim_names.h to clean-files:
* rework cmd_make-XXX to make them more readable by adding comments,
  reworking the expressions to put logical components on individual lines,
  and keep lines < 80 characters.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>