Remove ELF filename argument.

We are embedding the ELF image in the Oat file.  We don't
need ELF filename anymore.

(cherry picked from commit b245ccacf447b014838535a7d8a58365642f0c3d)

Change-Id: I235429222401100c09381ba44a3978f38d5b499c
diff --git a/src/compiler_llvm/compilation_unit.cc b/src/compiler_llvm/compilation_unit.cc
index b73e997..3b4defd 100644
--- a/src/compiler_llvm/compilation_unit.cc
+++ b/src/compiler_llvm/compilation_unit.cc
@@ -194,16 +194,7 @@
     pm.run(*module_);
   }
 
-  // Write ELF image to file
-  // TODO: Remove this when we can embed the ELF image in the Oat file.
-  // We are keeping these code to run the unit test.
-  llvm::OwningPtr<llvm::tool_output_file> out_file(
-    new llvm::tool_output_file(elf_filename_.c_str(), errmsg,
-                               llvm::raw_fd_ostream::F_Binary));
-  out_file->os().write(elf_image_.data(), elf_image_.size());
-  out_file->keep();
-
-  LOG(INFO) << "ELF: " << elf_filename_ << " (done)";
+  LOG(INFO) << "Compilation Unit: " << elf_idx_ << " (done)";
 
   // Free the resources
   context_.reset(NULL);