[Atomics] Remove Atomics code stubs; use TF ops

src/mips/interface-descriptors-mips.cc

Index: src/mips/interface-descriptors-mips.cc
diff --git a/src/mips/interface-descriptors-mips.cc b/src/mips/interface-descriptors-mips.cc
index 17e8aecb172b464e8260c78c5f0f5f050b2c56d3..7ab2445744cf3ee1b98adfd3b7fbb26a10abdf3d 100644
--- a/src/mips/interface-descriptors-mips.cc
+++ b/src/mips/interface-descriptors-mips.cc
@@ -424,15 +424,6 @@ 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