[MLIR][ExecutionEngine] Don't create a _mlir_ wrapper function for internal linkage (llvm#171115)

This is somehow NFC, we were creating wrapper for interal functions,
which are de-facto not callable.

Author: joker-eph

mlir/lib/ExecutionEngine/ExecutionEngine.cpp

@@ -146,12 +146,10 @@ static void packFunctionArguments(Module *module) {
   llvm::IRBuilder<> builder(ctx);
   DenseSet<llvm::Function *> interfaceFunctions;
   for (auto &func : module->getFunctionList()) {
-    if (func.isDeclaration()) {
+    if (func.isDeclaration() || func.hasLocalLinkage())
       continue;
-    }
-    if (interfaceFunctions.count(&func)) {
+    if (interfaceFunctions.count(&func))
       continue;
-    }
 
     // Given a function `foo(<...>)`, define the interface function
     // `mlir_foo(i8**)`.