pgo_tools: remove --use from the PGO creation script

`--use` was primarily `use`d for generating llvm-next PGO profiles.
Since `USE=llvm-next` is gone, this flag can be removed.

BUG=b:335515781
TEST=repo upload

Change-Id: Ie730bf0d2ebb92342f912a834deddae76d7f516c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5479387
Commit-Queue: George Burgess <gbiv@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>
Reviewed-by: Bob Haarman <inglorion@chromium.org>
1 file changed