[ISSUE] Open MPI: mpiff77 doesn't -I/usr/include

[meator <meator@users.noreply.github.com>]

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New issue by meator on void-packages repository

https://github.com/void-linux/void-packages/issues/49322

Description:
### Is this a new report?

Yes

### System Info

Void 6.6.21_1 x86_64 GenuineIntel uptodate hold rrrdDFFFFFFFFFFFFFFFFFFFFFFFFFFFFF

### Package(s) Affected

openmpi-5.0.2_1

### Does a report exist for this bug with the project's home (upstream) and/or another distro?

_No response_

### Expected behaviour

Having the following code:

```fortran
      program main
#include "mpif.h"
       integer ierr
       call mpi_init(ierr)
      end
```

I expect it to compile with

```
mpif90 code.F90
```

Note that I didn't make up this code, it comes from a configure script of a library I'd like to package which tries to test whether fortran compiler works by compiling the aforementioned code.

### Actual behaviour

It doesn't compile. It however compiles with

```
mpif90 code.F90 -I/usr/include
```

To my knowledge (and please correct me if I'm wrong), `mpif90` (like all other MPI wrappers which link to `/usr/bin/opal_wrapper`) should wrap the underlying compiler while providing **all** flags needed for compiling with MPI.

```
mpif90 --showme
```

shows

```
gfortran -I/usr/lib64 -Wl,-rpath -Wl,/usr/lib64 -Wl,--enable-new-dtags -lmpi_usempif08 -lmpi_usempi_ignore_tkr -lmpi_mpifh -lmpi
```

which makes no mention of `/usr/include`.

I don't have proof of this, but I believe this is a regression, because it used to work in the past, so I assume an `openmpi` update broke it.

I've done some tests and it works without `-I/usr/include` on a Debian Docker container. Debian packages openmpi quite differently, its `--showme` looks like this:

```
gfortran -I/usr/lib/x86_64-linux-gnu/openmpi/lib/../../fortran/gfortran-mod-15/openmpi -I/usr/lib/x86_64-linux-gnu/openmpi/lib -L/usr/lib/x86_64-linux-gnu/openmpi/lib/fortran/gfortran -lmpi_usempif08 -lmpi_usempi_ignore_tkr -lmpi_mpifh -lmpi -lopen-rte -lopen-pal -lhwloc -levent_core -levent_pthreads -lm -lz
```

but it shows that it should work out of the box I believe.

Ping maintainer @ahesford 

### Steps to reproduce

Mentioned above.