Make clean target is removing files generated as part of tarball release

The AppArmor make clean target is removing files that were generated as part of the tarball release process.

Run the attached aa-make-clean.sh script and check the diffstat output.

$ ~/aa-make-clean.sh
make[1]: *** No rule to make target 'clean'. Stop.
find: ‘simple_tests/generated_dbus’: No such file or directory
Makefile:153:
 ************************************************************************
 No dbus pkg-config skipping dbus_eavesdrop dbus_message dbus_services tests ...
 Install libdbus-1-dev or equivalent package to build and run these tests
 ************************************************************************

 50 files changed, 10897 deletions(-)

It should show that no files are changed.