Add x86_64 support to the optimizing compiler.

Change-Id: I4462d9ae15be56c4a3dc1bd4d1c0c6548c1b94be
diff --git a/compiler/Android.mk b/compiler/Android.mk
index 4f9f312..6d2f5d1 100644
--- a/compiler/Android.mk
+++ b/compiler/Android.mk
@@ -84,6 +84,7 @@
 	optimizing/code_generator.cc \
 	optimizing/code_generator_arm.cc \
 	optimizing/code_generator_x86.cc \
+	optimizing/code_generator_x86_64.cc \
 	optimizing/graph_visualizer.cc \
 	optimizing/locations.cc \
 	optimizing/nodes.cc \