py : add Phi-1.5/Phi-2 tokenizer (#9361)

* add phi2 tokenizer

* add phi name to convert_hf_to_gguf_update.py

* make tokenizer_pre consistent; llama.cpp work

convert_hf_to_gguf.py

@@ -626,6 +626,9 @@ class Model:
         if chkhsh == "4e2b24cc4770243d65a2c9ec19770a72f08cffc161adbb73fcbb6b7dd45a0aae":
             # ref: https://huggingface.co/LGAI-EXAONE/EXAONE-3.0-7.8B-Instruct
             res = "exaone"
+        if chkhsh == "fcace8b9cac38ce847670c970cd5892031a753a1ef381abd1d9af00f713da085":
+            # ref: https://huggingface.co/microsoft/phi-2
+            res = "phi-2"
 
         if res is None:
             logger.warning("\n")