[SSSD] Use variable to control verbosity for things in common directory

[Ariel Barria]

https://fedorahosted.org/sssd/ticket/394

I was reviewing this ticket and talks about a default value to verbosity.

althought i'm not sure if is about the sssd debug level or other case.

If the case of debug level:

Reading theory in
   http://sgallagh.fedorapeople.org/sssd/1.8.91/man/sssd.conf.5.html 
in section debug_level (integer) mentions that:

  "0x0010 is the default value as well as the lowest allowed value"
  "0x0010: Fatal failures. Anything that would prevent SSSD from starting up or
causes it to cease running."

If you want to use a higher debug level is changed in sssd.conf-> debug_level =
(desired level is placed).

By not specifying on command line flag, is used the indicated in sssd.conf
->debug_level.

If specified in command line debug_level first uses the command line, this was corrected
in the ticket https://fedorahosted.org/sssd/ticket/764

In the case concerned from that, the flag already exists.

util.h
[code]
      /** \def DEBUG_IS_SET(level)
         \brief checks whether level (must be in new format) is set in debug_level
          \param level the debug level, please use one of the SSSDBG*_ macros
      */
       #define DEBUG_IS_SET(level) (debug_level & (level))
       
       #define CONVERT_AND_SET_DEBUG_LEVEL(new_value) debug_level = ( \
            ((new_value) != SSSDBG_INVALID) \
            ? debug_convert_old_level(new_value) \
            : SSSDBG_UNRESOLVED /* Debug level should be loaded from config file. */ \
       );
[/code]