Upgrade TBAA *before* upgrading intrinsics

Summary: If TBAA is on an intrinsic and it gets upgraded and drops the TBAA we hit an odd assert. We should just upgrade the TBAA first because it doesn't have side-effects.

Reviewers: reames, apilipenko, manmanren

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18229

llvm-svn: 263673