Suppress warnings in cuda/internal/ExecutionPolicy.h

This is where we call the thrust algorithms. There must be some loop
where it, on some code path, calls back a host function. This must be in
an execution path that never happens. The thrust version has its own
suppress, but that does not seem to actually suppress the warning (it
just means that the warning does not tell you where the actual call is).

Get around the problem by suppressing the warnings in VTK-m.
14 jobs for cuda-shared-no-virtual
Status Name Job ID Coverage
  External
passed cdash-buildbot

passed vtk-m-dragnipur-osx-shared-debug+32bit_ids+64bit_coords+clang+tbb

00:05:28

passed vtk-m-dragnipur-osx-static-release+64bit_coords+clang+tbb

00:08:28

passed vtk-m-osheim-windows-shared-debug+ninja-vs-2017+tbb

00:13:25

passed vtk-m-osheim-windows-static-release+ninja-vs-2017+tbb

00:21:30

passed cdash-buildbot

passed vtk-m-dragnipur-osx-shared-debug+32bit_ids+64bit_coords+clang+tbb

passed vtk-m-dragnipur-osx-shared-debug+32bit_ids+64bit_coords+clang+tbb

00:01:12

passed vtk-m-dragnipur-osx-static-release+64bit_coords+clang+tbb

00:00:15

passed vtk-m-dragnipur-osx-static-release+64bit_coords+clang+tbb

passed vtk-m-osheim-windows-shared-debug+ninja-vs-2017+tbb

passed vtk-m-osheim-windows-shared-debug+ninja-vs-2017+tbb

00:06:37

passed vtk-m-osheim-windows-static-release+ninja-vs-2017+tbb

passed vtk-m-osheim-windows-static-release+ninja-vs-2017+tbb

00:02:17