Suppress output from the dwp tool in link scripts.

- The output doesn't seem useful. When data is missing the tool
segfaults rather than printing a message.

Bug: 1122182
Change-Id: I46842793e831b02d169f8d3acc4fa82de3f77951
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2521846


Commit-Queue: Nelson Billing <nbilling@google.com>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824913}