Revert of [turbofan][arm64] Match fneg for -0.0 - x pattern.

Revert of [turbofan][arm64] Match fneg for -0.0 - x pattern. (patchset #1 id:1 of https://codereview.chromium.org/1013743006/)

Reason for revert:
Revert due to crash.

Original issue's description:
> [turbofan][arm64] Match fneg for -0.0 - x pattern.
>
> Note that this patch add an extra bit to the ArchOpcodeField.
>
> R=bmeurer@chromium.org
>
> Committed: https://crrev.com/fe7441225100660d01e66ce3bcaefe368f62df81
> Cr-Commit-Position: refs/heads/master@{#27494}

TBR=bmeurer@chromium.org,baptiste.afsa@arm.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/98580e4b8300abaa3891f8f4d48f94ff053b2924
Cr-Commit-Position: refs/heads/master@{#27495}

[Yang, 2015-03-27 09:11:32]

Created Revert of [turbofan][arm64] Match fneg for -0.0 - x pattern.

[Yang, 2015-03-27 09:11:42]

On 2015/03/27 09:11:32, Yang wrote:
> Created Revert of [turbofan][arm64] Match fneg for -0.0 - x pattern.

See
http://chromegw.corp.google.com/i/client.v8/builders/V8%20Linux%20-%20arm64%2...

[commit-bot: I haz the power, 2015-03-27 09:11:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1041633002/1

[commit-bot: I haz the power, 2015-03-27 09:11:56]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-27 09:12:13]

Patchset 1 (id:??) landed as
https://crrev.com/98580e4b8300abaa3891f8f4d48f94ff053b2924
Cr-Commit-Position: refs/heads/master@{#27495}