Revert of VectorICs: Turn on vector ICs for LOAD and KEYED_LOAD cases. (patchset #1 id:1 of https://codereview.chromium.org/1070653002/)

Reason for revert:
ARM test failure, need to investigate.

Original issue's description:
> VectorICs: Turn on vector ICs for LOAD and KEYED_LOAD cases.
>
> R=verwaest@chromium.org
> BUG=
>
> Committed: https://crrev.com/2395eda3bb7aca938751938df76e01ac2b89b0a6
> Cr-Commit-Position: refs/heads/master@{#27657}

TBR=verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/1072463002

Cr-Commit-Position: refs/heads/master@{#27664}