Add char to the list of supported scalar types for vtk-m.

Allison Piperrequested to merge
alliepiper16/vtk:handle_char_in_vtkm into master

VTK-m's scalar list contains Int8/UInt8 (signed char/unsigned char), but not char. Since VTK uses char, we need to handle them.

Backport: paraview/release

Edited by Allison Piper

Merge request reports