llvm_tools: tweak script verbosity

At the moment, this script is silent except for when gsutil sneakily
prints file copying status to stdout/stderr. Since we're already
configuring `logging` here, be a bit more descriptive about our current

TEST=Ran the script.

Change-Id: Ibcdb0f6cd488e70b9f810a9ca615556a7d672948
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2412481
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>
1 file changed