[Bug fortran/125584] gfortran.dg/corray tests may use excessive space in /tmp

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125584

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I would suggest to reduce the shmem segment size, 256MB per image seems
excessive.  Sth like 2MB is more reasonable.