Nuke the old JIT.

I am sure we will be finding bits and pieces of dead code for years to
come, but this is a good start.

Thanks to Lang Hames for making MCJIT a good replacement!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215111 91177308-0d34-0410-b5e6-96231b3b80d8

examples/ExceptionDemo/ExceptionDemo.cpp

@@ -1964,10 +1964,8 @@ int main(int argc, char *argv[]) {
   // Build engine with JIT
   llvm::EngineBuilder factory(module);
   factory.setEngineKind(llvm::EngineKind::JIT);
-  factory.setAllocateGVsWithCode(false);
   factory.setTargetOptions(Opts);
   factory.setMCJITMemoryManager(MemMgr);
-  factory.setUseMCJIT(true);
   llvm::ExecutionEngine *executionEngine = factory.create();
 
   {