[ELF] Deleted unused ComdatGroups member variable left by D61854

llvm-svn: 361266

Author: MaskRay

lld/ELF/SymbolTable.h

@@ -82,11 +82,6 @@ class SymbolTable {
   llvm::DenseMap<llvm::CachedHashStringRef, int> SymMap;
   std::vector<Symbol *> SymVector;
 
-  // Comdat groups define "link once" sections. If two comdat groups have the
-  // same name, only one of them is linked, and the other is ignored. This set
-  // is used to uniquify them.
-  llvm::DenseSet<llvm::CachedHashStringRef> ComdatGroups;
-
   // A map from demangled symbol names to their symbol objects.
   // This mapping is 1:N because two symbols with different versions
   // can have the same name. We use this map to handle "extern C++ {}"