Intrinsify System.arraycopy.

Currently on x64, will do the other architectures in
different changes.

Change-Id: I15fbbadb450dd21787809759a8b14b21b1e42624
diff --git a/compiler/optimizing/intrinsics_mips64.cc b/compiler/optimizing/intrinsics_mips64.cc
index b60905d..764a114 100644
--- a/compiler/optimizing/intrinsics_mips64.cc
+++ b/compiler/optimizing/intrinsics_mips64.cc
@@ -812,6 +812,7 @@
 UNIMPLEMENTED_INTRINSIC(ReferenceGetReferent)
 UNIMPLEMENTED_INTRINSIC(StringGetCharsNoCheck)
 UNIMPLEMENTED_INTRINSIC(SystemArrayCopyChar)
+UNIMPLEMENTED_INTRINSIC(SystemArrayCopy)
 
 #undef UNIMPLEMENTED_INTRINSIC