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

Summary:
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.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: echristo, zturner, samsonov

Reviewed By: echristo

Subscribers: JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45134

llvm-svn: 328935
diff --git a/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
index 9a3d3e3..bf9dd7c 100644
--- a/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
@@ -79,7 +79,7 @@
   for (const auto &M : Mappings)
     Ids.push_back(&M);
 
-  std::sort(Ids.begin(), Ids.end(), [this](const T &L1, const T &L2) {
+  llvm::sort(Ids.begin(), Ids.end(), [this](const T &L1, const T &L2) {
     return Strings.getIdForString(L1->getKey()) <
            Strings.getIdForString(L2->getKey());
   });