toolchain: rename *_ORDERING_FILE artifacts

For consistency, rename the artifacts from ..._ORDERING_FILE to
..._CHROME_LLVM_ORDERFILE.

See also crrev.com/c/2057381/8/lib/toolchain_util.py#1341

BUG=chromium:1019868
TEST=generate.

Change-Id: Iac95cae238fff39c47b41ff3a5e31c12a810c56a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2066942
Reviewed-by: David Burger <dburger@chromium.org>
Commit-Queue: LaMont Jones <lamontjones@chromium.org>
Tested-by: LaMont Jones <lamontjones@chromium.org>
3 files changed