art: Handle x86_64 architecture equal to x86

This patch forces FE/ME to treat x86_64 as x86 exactly.
The x86_64 logic will be revised later when assembly will be ready.

Change-Id: I4a92477a6eeaa9a11fd710d35c602d8d6f88cbb6
Signed-off-by: Dmitry Petrochenko <dmitry.petrochenko@intel.com>
diff --git a/compiler/optimizing/code_generator.cc b/compiler/optimizing/code_generator.cc
index b86665b..2207fd7 100644
--- a/compiler/optimizing/code_generator.cc
+++ b/compiler/optimizing/code_generator.cc
@@ -112,6 +112,9 @@
     case kX86: {
       return new (allocator) x86::CodeGeneratorX86(graph);
     }
+    case kX86_64: {
+      return new (allocator) x86::CodeGeneratorX86(graph);
+    }
     default:
       return nullptr;
   }