Update linux sysroot image

Update linux sysroot image

This adds libffi-dev and libdrm-dev to the image
which were recently added with:
https://codereview.chromium.org/1464123002

R=thestig@chromium.org
BUG=559062
Committed: https://crrev.com/24634402107d104bc23e018593f7dcbcb78be081
Cr-Commit-Position: refs/heads/master@{#361129}

[Sam Clegg, 2015-11-23 16:54:45]

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

[Lei Zhang, 2015-11-23 16:55:37]

lgtm

[commit-bot: I haz the power, 2015-11-23 16:55:51]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1466383002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1466383002/1

[commit-bot: I haz the power, 2015-11-23 17:08:36]

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

[commit-bot: I haz the power, 2015-11-23 17:08:37]

Dry run: This issue passed the CQ dry run.

[Sam Clegg, 2015-11-23 17:09:42]

The CQ bit was checked by sbc@chromium.org

[commit-bot: I haz the power, 2015-11-23 17:10:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1466383002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1466383002/1

[commit-bot: I haz the power, 2015-11-23 17:16:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-23 17:18:20]

Patchset 1 (id:??) landed as
https://crrev.com/24634402107d104bc23e018593f7dcbcb78be081
Cr-Commit-Position: refs/heads/master@{#361129}