Revert of [turbofan] Take the immediate size in account when narrowing ia32/x64 word comparison operators. (patchset #1 id:1 of https://codereview.chromium.org/1968453002/ )

Reason for revert:
Breaks a KCS demo:

BUG=chromium:611976

Original issue's description:
> [turbofan] Take the immediate size in account when narrowing ia32/x64 word comparison operators.
>
> Trying to re-land http://crrev.com/1948453002 after fixing assembler-x64.cc in http://crrev.com/1962563003.
>
> Before this patch, we would emit a cmp or test with a memory operand only if both of the operands in the IR were loads. Now if either of them is a load and the other one is an immediate, we can use a memory operand if the load representation machine size is wide enough to represent the latter.
>
> Committed: https://crrev.com/2da70f853d7f680d491c37c72d5ef04a85497ba9
> Cr-Commit-Position: refs/heads/master@{#36136}

TBR=bmeurer@chromium.org,epertoso@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.

Review-Url: https://codereview.chromium.org/1995303003
Cr-Commit-Position: refs/heads/master@{#36413}