Fix art test failures for Mips.

This patch fixes the following art test failures for Mips:
003-omnibus-opcodes
030-bad-finalizer
041-narrowing
059-finalizer-throw

Change-Id: I4e0e9ff75f949c92059dd6b8d579450dc15f4467
Signed-off-by: Douglas Leung <douglas@mips.com>
diff --git a/runtime/entrypoints/quick/quick_entrypoints.h b/runtime/entrypoints/quick/quick_entrypoints.h
index 032f6be..473687c 100644
--- a/runtime/entrypoints/quick/quick_entrypoints.h
+++ b/runtime/entrypoints/quick/quick_entrypoints.h
@@ -138,6 +138,10 @@
   void (*pThrowNoSuchMethod)(int32_t);
   void (*pThrowNullPointer)();
   void (*pThrowStackOverflow)(void*);
+
+  // Atomic 64-bit load/store
+  int64_t (*pA64Load)(volatile const int64_t *);
+  void (*pA64Store)(volatile int64_t *, int64_t);
 };