Configure failure detecting logical kinds for MPI

[DJDavies2]

Describe the bug

Running configure with --enable-fortran and --enable-parallel fails like this:

configure: error: Failed to find Fortran KIND of LOGICAL in MPI

Expected behavior

Configure should work.

Platform (please complete the following information)

• HDF5 version: 1.14.4.3
• OS and version: RHEL7 Linux
• Compiler and version: gnu 9.2.0
• Build system (e.g. CMake, Autotools) and version: autotools
• Any configure options you specified: --enable-fortran --enable-parallel
• MPI library and version (parallel HDF5): mpich 4.2.2

Additional context

In the past we have passed the location of the MPI library by setting FCFLAGS. However it looks like the configure script is doing this:

saved_FCFLAGS=$FCFLAGS check_Intel="$FC -V 2>&1 |grep '^Intel'" if test X != "X$check_Intel"; then FCFLAGS="-warn error" else FCFLAGS="" fi

This means that the FCFLAGS gets unset resulting in this compile line being executed:

configure:33247: gfortran -c conftest.f90 >&5

which fails as it cannot find the MPI module.