Update comments to include addrspacecast

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212961 91177308-0d34-0410-b5e6-96231b3b80d8
Add CreatePointerBitCastOrAddrSpaceCast to IRBuilder and co.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212962 91177308-0d34-0410-b5e6-96231b3b80d8