intel_shader_integer_functions2 mingw-w64 i686 build errors

The AppVeyor mingw-w64 i686 build started failing with the intel_shader_integer_functions2 changes.

https://ci.appveyor.com/project/mesa3d/piglit/builds/29953293

[3324/3343] Generating intel_shader_integer_functions2_tests.list
FAILED: generated_tests/intel_shader_integer_functions2_tests.list 
cmd.exe /C "cd /D C:\projects\piglit\build\generated_tests && C:\Python36\python.exe C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py > intel_shader_integer_functions2_tests.list"
C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py:83: RuntimeWarning: overflow encountered in long_scalars
  return np.uint32(a - b) if a > b else np.uint32(b - a)
Traceback (most recent call last):
  File "C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py", line 792, in <module>
    main()
  File "C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py", line 786, in main
    results=attrib['results'](attrib['sources'](), attrib['operator']),
  File "C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py", line 44, in generate_results_commutative
    results.append(operator(srcs[i], srcs[j]))
  File "C:/projects/piglit/generated_tests/gen_intel_shader_integer_functions2_tests.py", line 81, in abs_isub32
    b = np.int32(_b)
OverflowError: Python int too large to convert to C long