Use llvm::cast instead of reinterpret_cast.
Also, GetElementPtrInst::getType() method returns SequentialType now, instead of
PointerType. There wasn't any issue yet, so no testcase attached.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175452 91177308-0d34-0410-b5e6-96231b3b80d8