`PMP::split_long_edges` fails to compile with Epeck kernel

[dpapavas]

The following test program fails to compile:

#include <CGAL/Exact_predicates_exact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/Polygon_mesh_processing/remesh.h>

typedef CGAL::Exact_predicates_exact_constructions_kernel   K;
// typedef CGAL::Surface_mesh<K::Point_3>                      Mesh;
typedef CGAL::Polyhedron_3<K>                      Mesh;
namespace PMP = CGAL::Polygon_mesh_processing;

int main(int argc, char* argv[])
{
  Mesh mesh;

  double target_edge_length = 1.0;

  PMP::split_long_edges(CGAL::edges(mesh), target_edge_length, mesh);
  return 0;
}

I've tried both v6.0.1 and v6.1.1 with the same results. Compilation fails with either Polyhedron_3 or Surface_mesh, but it succeeds with the Epick kernel. This is most likely related to this issue, where changes have been applied to only one of the two versions of split_long_edges. This patch seems to fix it, but more changes might be needed.