Fix 'gcc -flto' builds for unittest binaries (undefined reference to

`typeinfo for llvm::cl::GenericOptionValue').

Remove an "anchor" method for an abstract class. (This does not
increase the number of vtables.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183830 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/CommandLine.cpp

@@ -59,7 +59,6 @@ TEMPLATE_INSTANTIATION(class opt<char>);
 TEMPLATE_INSTANTIATION(class opt<bool>);
 } } // end namespace llvm::cl
 
-void GenericOptionValue::anchor() {}
 void OptionValue<boolOrDefault>::anchor() {}
 void OptionValue<std::string>::anchor() {}
 void Option::anchor() {}