[vtkusers] vtkImageDataToTkPhoto - build errors on WinNT VC6

[anast.jm at pg.com]

I'm getting build error on todays cvs (WinNT4, VC6) apparently related to recent
addition of ToTkPhoto code. I deleted the emails on this code before I got the
link errors so can't remember who submitted the code.....john

--------------------Configuration: vtkRenderingTCL - Win32 Release--------------------
Linking...
   Creating library P:\WinCVS\vtk40\VTKbin\bin\Release/vtkRenderingTCL.lib and object P:\WinCVS\vtk40\VTKbin\bin\Release/vtkRenderingTCL.exp
vtkTkRenderWidget.obj : error LNK2001: unresolved external symbol _vtkImageDataToTkPhoto_Cmd
P:\WinCVS\vtk40\VTKbin\bin\Release/vtkRenderingTCL.dll : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

ALL_BUILD - 2 error(s), 0 warning(s)