[PATCH, committed] Fix editorial error and new test case

[Jerry D]

Following push as obvious.

Regression tested on x86_64.
Cheers,

Jerry

commit 4d9a71ceec40da31f781a495368250a1b92d5acb (HEAD -> master, origin/master, 
origin/HEAD)
Author: Jerry DeLisle <jvdeli...@gcc.gnu.org>
Date:   Sun Jul 26 13:33:07 2026 -0700

    fortran: Fix editorial error and new test case

    libgfortran/ChangeLog:

            * intrinsics/reduce.c (reduce): Fix the mask_present.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/reduce_5.f90: Verify the previously dead
            code error message occurs.