Fix PR3452 (an infinite loop bootstrapping) by disabling the recent

Fix PR3452 (an infinite loop bootstrapping) by disabling the recent
improvements to the EvaluateInDifferentType code.  This code works
by just inserted a bunch of new code and then seeing if it is
useful.  Instcombine is not allowed to do this: it can only insert
new code if it is useful, and only when it is converging to a more
canonical fixed point.  Now that we iterate when DCE makes progress,
this causes an infinite loop when the code ends up not being used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63483 91177308-0d34-0410-b5e6-96231b3b80d8