[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.

Remove the old functions.

llvm-svn: 202636
diff --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
index 32207b2..5c481fb 100644
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -693,7 +693,7 @@
     NonLocalDepInfo::iterator Entry =
       std::upper_bound(Cache.begin(), Cache.begin()+NumSortedEntries,
                        NonLocalDepEntry(DirtyBB));
-    if (Entry != Cache.begin() && prior(Entry)->getBB() == DirtyBB)
+    if (Entry != Cache.begin() && std::prev(Entry)->getBB() == DirtyBB)
       --Entry;
 
     NonLocalDepEntry *ExistingResult = 0;