[clang] Change std::sort to llvm::sort in response to r327219

r327219 added wrappers to std::sort which randomly shuffle the container before
sorting.  This will help in uncovering non-determinism caused due to undefined
sorting order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of
std::sort.

llvm-svn: 328636
diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 466253c..45c0ec4 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -8513,7 +8513,7 @@
     // The ABI requires unions to be sorted but not structures.
     // See FieldEncoding::operator< for sort algorithm.
     if (RT->isUnionType())
-      std::sort(FE.begin(), FE.end());
+      llvm::sort(FE.begin(), FE.end());
     // We can now complete the TypeString.
     unsigned E = FE.size();
     for (unsigned I = 0; I != E; ++I) {
@@ -8557,7 +8557,7 @@
       EnumEnc += '}';
       FE.push_back(FieldEncoding(!I->getName().empty(), EnumEnc));
     }
-    std::sort(FE.begin(), FE.end());
+    llvm::sort(FE.begin(), FE.end());
     unsigned E = FE.size();
     for (unsigned I = 0; I != E; ++I) {
       if (I)