ppcg.c: compute_tagged_flow_dep: use isl_union_map_factor_domain
ppcg.c: compute_tagged_flow_dep: use isl_union_map_factor_domain

Signed-off-by: Sven Verdoolaege <e5350bbed4977f5eb8ae1dc6abd9ae59d21ace75@kotnet.org>

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