[Polly] Fix code generation of llvm.expect intrinsic

At the time of code generation, an instruction with an llvm intrinsic is ignored
in copyBB. However, if the value of the instruction is used later in the
program, the value needs to be synthesized. However, this is causing some issues
with the instructions being generated in a hoisted basic block.

Removing llvm.expect from the list of ignored intrinsics fixes this bug.

This resolves http://llvm.org/PR32324

.

Contributed-by: Annanay Agarwal <cs14btech11001@iith.ac.in>

Tags: #polly

Differential Revision: https://reviews.llvm.org/D32992

llvm-svn: 303006