Add tests for Arm64RelativePatcher.

Change-Id: I9d2c21d323137ac143eabb8fdf6ca075bae45c51
diff --git a/build/Android.gtest.mk b/build/Android.gtest.mk
index f834a38..1e7988a 100644
--- a/build/Android.gtest.mk
+++ b/build/Android.gtest.mk
@@ -193,6 +193,7 @@
   compiler/elf_writer_test.cc \
   compiler/image_test.cc \
   compiler/jni/jni_compiler_test.cc \
+  compiler/linker/arm64/relative_patcher_arm64_test.cc \
   compiler/linker/arm/relative_patcher_thumb2_test.cc \
   compiler/linker/x86/relative_patcher_x86_test.cc \
   compiler/linker/x86_64/relative_patcher_x86_64_test.cc \