ARM64: Add support for multiply-accumulate.

Change-Id: I88dc313df520480f3fd16bbabda27f9435d25368
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 4f894b0..f36e0f5 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -1096,7 +1096,8 @@
 #define FOR_EACH_CONCRETE_INSTRUCTION_ARM64(M)
 #else
 #define FOR_EACH_CONCRETE_INSTRUCTION_ARM64(M)                          \
-  M(Arm64IntermediateAddress, Instruction)
+  M(Arm64IntermediateAddress, Instruction)                              \
+  M(Arm64MultiplyAccumulate, Instruction)
 #endif
 
 #define FOR_EACH_CONCRETE_INSTRUCTION_MIPS(M)