Make TORCH_SHOW_DISPATCH_TRACE actually work (#82277)
It looks like DEBUG macro is never actually set anywhere, see
https://github.com/pytorch/pytorch/issues/82276
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/82277
Approved by: https://github.com/malfet
