[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/utils/TableGen/ClangOptionDocEmitter.cpp b/clang/utils/TableGen/ClangOptionDocEmitter.cpp
index 734ff0b..7fe487e 100644
--- a/clang/utils/TableGen/ClangOptionDocEmitter.cpp
+++ b/clang/utils/TableGen/ClangOptionDocEmitter.cpp
@@ -111,7 +111,7 @@
 
   auto DocumentationForOption = [&](Record *R) -> DocumentedOption {
     auto &A = Aliases[R];
-    std::sort(A.begin(), A.end(), CompareByName);
+    llvm::sort(A.begin(), A.end(), CompareByName);
     return {R, std::move(A)};
   };
 
@@ -120,7 +120,7 @@
     Documentation D;
 
     auto &Groups = GroupsInGroup[R];
-    std::sort(Groups.begin(), Groups.end(), CompareByLocation);
+    llvm::sort(Groups.begin(), Groups.end(), CompareByLocation);
     for (Record *G : Groups) {
       D.Groups.emplace_back();
       D.Groups.back().Group = G;
@@ -129,7 +129,7 @@
     }
 
     auto &Options = OptionsInGroup[R];
-    std::sort(Options.begin(), Options.end(), CompareByName);
+    llvm::sort(Options.begin(), Options.end(), CompareByName);
     for (Record *O : Options)
       D.Options.push_back(DocumentationForOption(O));