Mark __jit_debug_register_code as a unique symbol on aarch64

The symbol have been marked as unique on arm, x86, x86_64 already.
This change mark it as unique on aarch64 as well because we switched
to gold linker and enabled identical code folding (ICF) for aarch64
also.

Change-Id: I3575e2db4ba4933fcc173eaaab6962881a7c9800
diff --git a/runtime/Android.mk b/runtime/Android.mk
index 288f95e..eaba333 100644
--- a/runtime/Android.mk
+++ b/runtime/Android.mk
@@ -238,6 +238,7 @@
 # (empty) body is called.
 JIT_DEBUG_REGISTER_CODE_LDFLAGS := -Wl,--keep-unique,__jit_debug_register_code
 LIBART_TARGET_LDFLAGS_arm    := $(JIT_DEBUG_REGISTER_CODE_LDFLAGS)
+LIBART_TARGET_LDFLAGS_arm64  := $(JIT_DEBUG_REGISTER_CODE_LDFLAGS)
 LIBART_TARGET_LDFLAGS_x86    := $(JIT_DEBUG_REGISTER_CODE_LDFLAGS)
 LIBART_TARGET_LDFLAGS_x86_64 := $(JIT_DEBUG_REGISTER_CODE_LDFLAGS)
 JIT_DEBUG_REGISTER_CODE_LDFLAGS :=