Fix some malformed if !defined() header guards

Profiling: Improve !defined(PETSC_USE_LOG) #defines

- If we cast macro arguments to void, we can avoid unused errors that have
forced lots of conditionally included code like this:

```c
#if def

Profiling: Improve !defined(PETSC_USE_LOG) #defines

- If we cast macro arguments to void, we can avoid unused errors that have
forced lots of conditionally included code like this:

```c
#if defined(PETSC_USE_LOG)
PetscLogEvent event;
#endif
```

- Having global counters like petsc_TotalFlops externed event
if !PetscDefined(USE_LOG) helps to remove a lot of needless
`#ifdef`s around code that can instead be placed in
`if (PetscDefined(USE_LOG)) {}` blocks.

show more ...

Remove unneeded output files

Fix PetscCallMPI(MPI_Allreduce()) with PETSc types