isl_set_has_equal_space: implement in terms of isl_map_has_equal_space
isl_set_has_equal_space: implement in terms of isl_map_has_equal_space

This removes some (minor) code duplication.

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

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