Cleaning up unreachable code in CodeLayout

[spupyrev]

Summary

• removing an unreachable instruction from the code (earlier code merge bug);
• silencing "unused variable" warnings.

[spupyrev]

get rid of unused variables

llvm/lib/Transforms/Utils/CodeLayout.cpp

std::sort(SortedChains.begin(), SortedChains.end(),
               [&](const ChainT *L, const ChainT *R) {
                 // Place the entry point is at the beginning of the order.
                 if (L->isEntry() != R->isEntry())
                   return L->isEntry();
 
                 const double DL = ChainDensity[L];
                 const double DR = ChainDensity[R];
                 // Compare by density and break ties by chain identifiers.
-                return (DL != DR) ? (DL > DR) : (L->Id < R->Id);
                 return std::make_tuple(-DL, L->Id) <
                        std::make_tuple(-DR, R->Id);
               });
 
     // Collect the nodes in the order specified by their chains.
     Order.reserve(NumNodes);
     for (const ChainT *Chain : SortedChains) {
       for (NodeT *Node : Chain->Nodes) {