Revert 4334892e "[DAGCombine][ARM] x ==/!= c -> (x - c) ==/!= 0 iff '-c'...

Revert 4334892e "[DAGCombine][ARM] x ==/!= c  ->  (x - c) ==/!= 0  iff '-c' can be folded into the x node."

This broke various Windows builds, see comments on the Phabricator
review.

This also reverts the follow-up 20bf0cf2.

> Summary:
> This fold, helps recover from the rest of the D62266 ARM regressions.
> https://rise4fun.com/Alive/TvpC
>
> Note that while the fold is quite flexible, i've restricted it
> to the single interesting pattern at the moment.
>
> Reviewers: efriedma, craig.topper, spatel, RKSimon, deadalnix
>
> Reviewed By: deadalnix
>
> Subscribers: javed.absar, kristof.beyls, llvm-commits
>
> Tags: #llvm
>
> Differential Revision: https://reviews.llvm.org/D62450