jit: Initialize native parser so rust-repl works

Author: z0w0

src/rustllvm/RustWrapper.cpp

@@ -342,6 +342,7 @@ LLVMRustExecuteJIT(void* mem,
 
   InitializeNativeTarget();
   InitializeNativeTargetAsmPrinter();
+  InitializeNativeTargetAsmParser();
 
   std::string Err;
   TargetOptions Options;