[Atomics] Remove Atomics code stubs; use TF ops

src/mips64/interface-descriptors-mips64.cc

Index: src/mips64/interface-descriptors-mips64.cc
diff --git a/src/mips64/interface-descriptors-mips64.cc b/src/mips64/interface-descriptors-mips64.cc
index 28a66996833351528004520a440658ca849e275d..18d6f0f67dc02a1b34d28acc8d2c0d1809ad0162 100644
--- a/src/mips64/interface-descriptors-mips64.cc
+++ b/src/mips64/interface-descriptors-mips64.cc
@@ -423,15 +423,6 @@ void ResumeGeneratorDescriptor::InitializePlatformSpecific(
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
-void AtomicsLoadDescriptor::InitializePlatformSpecific(
-    CallInterfaceDescriptorData* data) {
-  Register registers[] = {
-      a1,  // the typedarray object
-      a0   // the index to load (untagged)
-  };
-  data->InitializePlatformSpecific(arraysize(registers), registers);
-}
-
 }  // namespace internal
 }  // namespace v8