Very few operations were missing in Nucleus for integer types
support, but there were a few nonetheless, so Int4 and UInt4
now have new operators: divide, modulo, right shift (from non
constant) and left shift (from non constant).

These were simply un-commented out as they were already there,
just commented out.

Change-Id: I4c124c9297cd4d3d755c37f11168a43dcfeee290
Reviewed-on: https://swiftshader-review.googlesource.com/3886Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>