isl_map_subtract.c: n_non_redundant: fix typo in comment
isl_map_subtract.c: n_non_redundant: fix typo in comment

Signed-off-by: Sven Verdoolaege <235c10dd23b819f81cdc9756a251746bc184cab6@gmail.com>

Meinersbur/isl,Meinersbur/isl,Meinersbur/isl,Meinersbur/isl