DEBUG macro refactoring v4

[Nikolai Kondrashov]

Hi everyone,

Here is the 4th and I hope the last version of my DEBUG macro refactoring
patch set.

Changes from the last version:

     * Rebase on fresh master (761777f).
     * Fix invocations of the updated "debug_fn" function to not assume it
       filters by debug level (found by Jakub).
     * Add patch to update debug levels in "sss_semanage_error_callback".
     * Add patch to update debug level in a "backup_file" invocation.
     * Add patch to reflow the new "debug_fn" to make it match coding
       conventions better, as per Jakub's request (although I didn't make a
       separate function as it doesn't seem to be necessary).
     * Re-run both mass update scripts, instead of cherry-picking.
     * Remove mentions of old/new debug levels in the patch removing the
       conversion function (the last one).

I built and tested the final results with "chmake", but did no other tests.

Sincerely,
Nick