[BL/MPI] Wrap MPI_Init and Finalize calls

BaseLib/MPI.h

@@ -21,6 +21,26 @@
 namespace BaseLib::MPI
 {
 
+struct Setup
+{
+    Setup(int argc, char* argv[])
+    {
+#ifdef USE_PETSC
+        MPI_Init(&argc, &argv);
+#else
+        (void)argc;
+        (void)argv;
+#endif  // USE_PETSC
+    }
+
+    ~Setup()
+    {
+#ifdef USE_PETSC
+        MPI_Finalize();
+#endif  // USE_PETSC
+    }
+};
+
 #ifdef USE_PETSC
 struct Mpi
 {