correct precompile directive to test for variable definition rather
than true value. Correction to commit 01b658a3

This reverts commit cc242de3
That patch fixed bug 2745, but breaks tests 1.89 and 1.91 on
typical Xeon processors

Fix for uninitialized variable in task binding logic, could leave tasks
    with fewer CPUs than intended.
bug 2766

Without this change, allocations less than a whole node can result
in an incorrect task binding for power7 processors

 Added printf __attribute__ qualifiers to info, debug, ... to help prevent bad/incorrect parameters being sent to them.  Original patch from Eygene Ryabinkin <rea+slurm@grid.kiae.ru>

    support writing scheduling events to a separate log file.

did not request a specific binding and the job was allocated the whole node

    a set of CPUs that belong NUMA locality domain with the appropriate
    --cpu-bind option (ldoms, rank_ldom, map_ldom, and mask_ldom), see
    "man srun" for more information.

    Cpuset libary must be installed and set "TaskPluginParam=cpusets"
    in slurm.conf to enable.
    NOTE: Currently disabled until additional testing is performed. 
    Enable by changing "HAVE_CPUSETTS_EXP" to "HAVE_CPUSETS" in
    src/plugins/task/affinity/*.[ch].

    task counts, patch.1.2.0-pre9.061212.cpubind_verbose from Dan Palermo (HP).

    http://www.open-mpi.org/software/plpa).

libc version which is not always reliable for this.

    Palermo, HP).