Avoid use of Python distutils.dir_util (#3203)
Avoid use of Python distutils.dir_util (#3203)

Required for compatibility with (some?) Python3 installations.
dneto0/SPIRV-Tools,dneto0/SPIRV-Tools,pierremoreau/SPIRV-Tools,KhronosGroup/SPIRV-Tools,dneto0/SPIRV-Tools,KhronosGroup/SPIRV-Tools,KhronosGroup/SPIRV-Tools,pierremoreau/SPIRV-Tools,dneto0/SPIRV-Tools,dneto0/SPIRV-Tools,dneto0/SPIRV-Tools,dneto0/SPIRV-Tools,KhronosGroup/SPIRV-Tools,KhronosGroup/SPIRV-Tools,pierremoreau/SPIRV-Tools,pierremoreau/SPIRV-Tools,pierremoreau/SPIRV-Tools,KhronosGroup/SPIRV-Tools,KhronosGroup/SPIRV-Tools,pierremoreau/SPIRV-Tools,dneto0/SPIRV-Tools,pierremoreau/SPIRV-Tools,pierremoreau/SPIRV-Tools,KhronosGroup/SPIRV-Tools