Suppress stderr on mesa package detection in install_build_deps.sh

Suppress stderr on mesa package detection in install_build_deps.sh

dpks-query is spamming stderr when the packages we query are not found.
Silencing stderr for dpkg-query.

BUG=429719
NOTRY=true

Committed: https://crrev.com/b83ed9b4f2089e06fa6aa1808f85eae7c34ebd01
Cr-Commit-Position: refs/heads/master@{#302457}

[Primiano Tucci (use gerrit), 2014-11-03 18:31:29]

primiano@chromium.org changed reviewers:
+ wtc@chromium.org

[wtc, 2014-11-03 18:37:09]

Patch set 1 LGTM. Thanks.

[Primiano Tucci (use gerrit), 2014-11-03 19:00:01]

The CQ bit was checked by primiano@chromium.org

[commit-bot: I haz the power, 2014-11-03 19:01:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/695373002/1

[commit-bot: I haz the power, 2014-11-03 19:02:57]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-03 19:03:41]

Patchset 1 (id:??) landed as
https://crrev.com/b83ed9b4f2089e06fa6aa1808f85eae7c34ebd01
Cr-Commit-Position: refs/heads/master@{#302457}