mpiCheckPhaseHook: add new setup hook for MPI aware check phases

Add this hook to checkPhase to allow for running MPI application in
the sandbox. It detects the MPI implementations and sets the respective
environment variables.

doc/hooks/mpi-check-hook.section.md

@@ -0,0 +1,24 @@
+#  mpiCheckPhaseHook {#setup-hook-mpi-check}
+
+
+This hook can be used to setup a check phase that
+requires running a MPI application. It detects the
+used present MPI implementaion type and exports
+the neceesary environment variables to use
+`mpirun` and `mpiexec` in a Nix sandbox.
+
+
+Example:
+
+```nix
+  { mpiCheckPhaseHook, mpi, ... }:
+
+  ...
+
+  nativeCheckInputs = [
+    openssh
+    mpiCheckPhaseHook
+  ];
+```
+
+