[Atomics] Remove Atomics code stubs; use TF ops

src/arm64/interface-descriptors-arm64.cc

Index: src/arm64/interface-descriptors-arm64.cc
diff --git a/src/arm64/interface-descriptors-arm64.cc b/src/arm64/interface-descriptors-arm64.cc
index 42e224992e53e12b7ab7aa32f15349adfb3f9541..0c3fbd5ffe7c406f83e6cf7feb3b2144861e6b86 100644
--- a/src/arm64/interface-descriptors-arm64.cc
+++ b/src/arm64/interface-descriptors-arm64.cc
@@ -477,15 +477,6 @@ void ResumeGeneratorDescriptor::InitializePlatformSpecific(
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
-void AtomicsLoadDescriptor::InitializePlatformSpecific(
-    CallInterfaceDescriptorData* data) {
-  Register registers[] = {
-      x1,  // the typedarray object
-      x0   // the index to load (untagged)
-  };
-  data->InitializePlatformSpecific(arraysize(registers), registers);
-}
-
 }  // namespace internal
 }  // namespace v8