Fix phi-3-mini build (#5513)

Summary:
Fix the build errors I introduced in pytorch/executorch#5318

Pull Request resolved: pytorch/executorch#5513

Test Plan: Built the model using the instructions at https://github.com/pytorch/executorch/blob/main/examples/models/phi-3-mini/README.md

Reviewed By: helunwencser

Differential Revision: D63133231

Pulled By: dbort

fbshipit-source-id: 81d5402e76fd86c919a13a1b1b83687feca72ab7

Author: dbort

examples/models/phi-3-mini/main.cpp

@@ -42,7 +42,7 @@ int main(int32_t argc, char** argv) {
 
   int32_t seq_len = FLAGS_seq_len;
 
-  ::torch::executor::Runner runner(model_path, tokenizer_path, temperature);
+  example::Runner runner(model_path, tokenizer_path, temperature);
 
   runner.generate(prompt, seq_len);
 

examples/models/phi-3-mini/runner.cpp

@@ -15,6 +15,12 @@
 #include <executorch/extension/tensor/tensor.h>
 #include <executorch/runtime/platform/log.h>
 
+using executorch::aten::ScalarType;
+using executorch::extension::Module;
+using executorch::extension::llm::BPETokenizer;
+using executorch::extension::llm::Sampler;
+using executorch::runtime::Error;
+
 namespace example {
 
 #define SAMPLER_TOP 0.9f

examples/models/phi-3-mini/runner.h

@@ -42,9 +42,9 @@ class Runner {
   uint64_t prefill(std::vector<uint64_t>& tokens);
   uint64_t run_model_step(uint64_t token);
 
-  std::unique_ptr<Module> module_;
-  std::unique_ptr<Tokenizer> tokenizer_;
-  std::unique_ptr<Sampler> sampler_;
+  std::unique_ptr<executorch::extension::Module> module_;
+  std::unique_ptr<executorch::extension::llm::Tokenizer> tokenizer_;
+  std::unique_ptr<executorch::extension::llm::Sampler> sampler_;
 };
 
 } // namespace example