Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges."

This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build.  I'll reply on the list in a moment.

llvm-svn: 213562
diff --git a/llvm/lib/IR/BasicBlock.cpp b/llvm/lib/IR/BasicBlock.cpp
index 8ddcf25..ba07433 100644
--- a/llvm/lib/IR/BasicBlock.cpp
+++ b/llvm/lib/IR/BasicBlock.cpp
@@ -321,9 +321,10 @@
   // successors.  If there were PHI nodes in the successors, then they need to
   // know that incoming branches will be from New, not from Old.
   //
-  for (BasicBlock *Successor : successors(New)) {
+  for (succ_iterator I = succ_begin(New), E = succ_end(New); I != E; ++I) {
     // Loop over any phi nodes in the basic block, updating the BB field of
     // incoming values...
+    BasicBlock *Successor = *I;
     PHINode *PN;
     for (BasicBlock::iterator II = Successor->begin();
          (PN = dyn_cast<PHINode>(II)); ++II) {