[Bug libfortran/124293] [caf_shmem] Some older systems do not have dprintf

[vehre at gmx dot de via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124293

--- Comment #3 from Andre Vehreschild <vehre at gmx dot de> ---
Go for it. Using dprintf() was taken from the original implementation and 
not my favorite. I don't know why I didn't scrap it.