[Fortran-dev][Patch] Fix cshift1

[Thomas Koenig]

Hi Tobias,

> This patch fixes the stride setting for cshift1; hence, it fixes
> gfortran.dg/optional_dim_3.f90.
>
> Build and regtested on x86-64-linux - 13 failing tests remain.
> OK?

OK. Thanks for the patch!

	Thomas