Comply llama2 runner with gcc 11.4 (#3140)

Summary:
Pull Request resolved: #3140

This seems like a simple change so that it can compile with gcc 11.4

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Reviewed By: digantdesai

Differential Revision: D56320381

fbshipit-source-id: 577a60bac78ed01ad450fcb58dbccc7f04fd5067

Author: mergennachin

extension/module/module.cpp

@@ -51,8 +51,8 @@ Module::Module(
     std::unique_ptr<EventTracer> event_tracer)
     : data_loader_(std::move(data_loader)),
       memory_allocator_(
-          std::move(memory_allocator)
-              ?: std::make_unique<util::MallocMemoryAllocator>()),
+          memory_allocator ? std::move(memory_allocator)
+                           : std::make_unique<util::MallocMemoryAllocator>()),
       event_tracer_(std::move(event_tracer)) {
   runtime_init();
 }