Dear Fortranners,

committed as obvious after regtesting on x86_64-pc-linux-gnu.

We already had a check for the MOLD argument to the TRANSFER
intrinsic for having storage size 0, which failed if MOLD was
an EXPR_VARIABLE although having rank != 0.  Duh.
Adjusting that check fixed the issue.

I intend to backport to the affected branches after some
waiting time.

Thanks,
Harald