llvm_tools: remove future import

Now that we're guaranteed to be on py3, this isn't
needed. Mostly doing this to test a crbug feature.

Fixed: 1109998

BUG=chromium:1109998
TEST=None

Change-Id: I1f5d0c9c7c1297e9281be07ced4127e42546b3c8
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2321109
Tested-by: George Burgess <gbiv@chromium.org>
Reviewed-by: Denis Nikitin <denik@chromium.org>
1 file changed