[Ozone-Drm] Remove GPU lock

[Ozone-Drm] Remove GPU lock

Workarounds to support grabbing the DRM devices as master after GPU crashes
made the GPU lock unnecessary.

BUG=none

Committed: https://crrev.com/5811284139852648ddc5e6332822de237e59ba8f
Cr-Commit-Position: refs/heads/master@{#330146}

[dnicoara, 2015-05-15 17:29:28]

dnicoara@chromium.org changed reviewers:
+ spang@chromium.org

[spang, 2015-05-15 17:42:40]

lgtm

please remove from frecon too

[dnicoara, 2015-05-15 17:47:44]

The CQ bit was checked by dnicoara@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-05-15 17:50:37]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1141243002/1

[commit-bot: I haz the power, 2015-05-15 18:24:46]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-05-15 18:24:47]

Dry run: This issue passed the CQ dry run.

[dnicoara, 2015-05-15 18:27:43]

The CQ bit was checked by dnicoara@chromium.org

[commit-bot: I haz the power, 2015-05-15 18:29:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1141243002/1

[commit-bot: I haz the power, 2015-05-15 18:39:57]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-15 18:40:42]

Patchset 1 (id:??) landed as
https://crrev.com/5811284139852648ddc5e6332822de237e59ba8f
Cr-Commit-Position: refs/heads/master@{#330146}