record 3d-FFT array packaging algorithm

src/lammps.cpp

@@ -1032,6 +1032,14 @@ static const char lammps_config_options[]
   " -DFFT_MKL"
 #else
   " -DFFT_KISSFFT"
+#endif
+  "\n3d-FFT data packing         :"
+#if defined(PACK_POINTER)
+  " -DPACK_POINTER"
+#elif defined(PACK_MEMCPY)
+  " -DPACK_MEMCPY"
+#else
+  " -DPACK_ARRAY"
 #endif
   "\nMemory alignment            :"
 #if defined(LAMMPS_MEMALIGN)