Comment/Remove Unused Parameters (#749)

Use the `clang-tidy` pass `misc-unused-parameters` to remove unused
parameter warnings.

https://clang.llvm.org/extra/clang-tidy/checks/misc-unused-parameters.html)

Committed as generic user so git does not credit the many lines to me:
```bash
GIT_AUTHOR_NAME="Tools" GIT_AUTHOR_EMAIL="warpx@lbl.gov"  \
  git commit
```

1 files changed, 6 insertions, 0 deletions

diff --git a/Source/Parallelization/GuardCellManager.cpp b/Source/Parallelization/GuardCellManager.cpp
index 0ec496861..8e4eca183 100644
--- a/Source/Parallelization/GuardCellManager.cpp
+++ b/Source/Parallelization/GuardCellManager.cpp
@@ -29,6 +29,12 @@ guardCellManager::Init(
     const amrex::Array<amrex::Real,3> v_galilean,
     const bool safe_guard_cells)
 {
+#ifndef WARPX_USE_PSATD
+    (void)do_fft_mpi_dec;
+    (void)nox_fft;
+    (void)noy_fft;
+    (void)noz_fft;
+#endif
     // When using subcycling, the particles on the fine level perform two pushes
     // before being redistributed ; therefore, we need one extra guard cell
     // (the particles may move by 2*c*dt)