Drop debugging message, full gres_alloc string is printed out already.

Rework prefix handling slightly.

Drop the debugging message here. The calling path above us prints
out the entire gres_alloc string, and I don't think it's necessary
to continue to break out the individual elements like this.

Rework the prefix (now sep) handling as well slightly.

Do a little cleanup around how the separator is handled while here.

Change _build_path to return the xmalloc()'d string, and make sure
to free it where appropriate.

Add comment about how the processing of the PATH environment variable
here is backwards from convention.

Fixes GCC 8.2.0 warnings.

Fix some -Werror=restrict and -Werror=format= issues.

Silence GCC 8.2.0 warning.

Nothing modifies this, so don't bother making a copy of it.

Related to GCC 8.2.0 compilation fixes.

Fixes GCC 8.2.0 compilation warnings.

Bug 5465.

improve some logs
correct comment formatting for linux kernel standard

this will happen if a job releases its resources to expand another job,
triggering a second epilog and slurmctld errors about cpu count underflows

state recovery for jobs with gres and topology was
previously incorrect

The NULL value logged was not unexpected for an
unused partition (initial state).

if each core has one thread, then remove whole cores from the
job allocation.
bug 5567

original was using env vars from batch host rather than using newly
set env vars from tasks spawned by srun

no real change in functionality

This schedules GPUs and craynetwork GRES for a single job

Fix some anomalies when scheduling multiple GRES for a single job
(e.g. GPUs plus craynetwork).

partially revert commit c6888db6d, which caused test39.5 to fail
with some configurations

Previous logic had an invalid pointer that could result in a segv.
Previous logic failed to properly allocate tres-per-node ot tres-per-job
without defining gres topology information

rather than just report GRES_IDX (index) info, report GRES count
info as well, since it can vary from node-to-node with cons_tres

This fixes a couple of bugs related to allocating GRES when
there is no associated topology, including adding support for
the --tres-per-job option