print_global_index: simplify expressions with respect to domain
print_global_index: simplify expressions with respect to domain

If an iterator has a fixed value, then no loop will be generated
and so we need to make sure that the expressions do not refer
to such an iterator.
We already perform such simplifications in print_local_index.

Reported-by: Carlos Juega Reimundez <0b2be4b3a81774f8c54c826fa1d60c3d1af16da8@fdi.ucm.es>
Signed-off-by: Sven Verdoolaege <e5350bbed4977f5eb8ae1dc6abd9ae59d21ace75@kotnet.org>

nicolasvasilache/ppcg,nicolasvasilache/ppcg,Meinersbur/ppcg,Meinersbur/ppcg