disable viskores on alpha

disable viskores on alpha

alpha is 64-bit but also exceeds available memory

[  5%] Generating the wrap hierarchy for VTK::ImagingCore
cd /build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/Imaging/Core && ../../bin/vtkWrapHierarchy-9.5 -MF /build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/Imaging/Core/CMakeFiles/vtkImagingCore-hierarchy.txt.d @/build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/Imaging/Core/CMakeFiles/vtkImagingCore-hierarchy.None.args -o /build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/lib/alpha-linux-gnu/vtk-9.5/hierarchy/VTK/vtkImagingCore-hierarchy.txt /build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/Imaging/Core/CMakeFiles/vtkImagingCore-hierarchy.data @/build/reproducible-path/vtk9-9.5.2+dfsg3/debian/build/Imaging/Core/CMakeFiles/vtkImagingCore-hierarchy.depends.args
/usr/bin/alpha-linux-gnu-ld.bfd: CMakeFiles/viskores_cont.dir/UnknownArrayHandle.cxx.o: .got subsegment exceeds 64K (size 96168)
/usr/bin/alpha-linux-gnu-ld.bfd: failed to set dynamic section sizes: no error