mtmd : Fix MinicpmV model converter and clip to avoid using hardcode. (#14750)

* Fix MinicpmV model converter and clip to avoid using hardcode.

* Code update for pr/14750

* Remove unused field, update script path in docs.

* Add version 5 for fallback code.

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Co-authored-by: lzhang <zhanglei@modelbest.cn>

docs/multimodal/minicpmo2.6.md

@@ -13,7 +13,7 @@ If there are differences in usage, please refer to the official build [documenta
 
 Clone llama.cpp:
 ```bash
-git clone https://github.com/ggerganov/llama.cpp
+git clone https://github.com/ggml-org/llama.cpp
 cd llama.cpp
 ```
 

docs/multimodal/minicpmv2.6.md

@@ -12,7 +12,7 @@ If there are differences in usage, please refer to the official build [documenta
 
 Clone llama.cpp:
 ```bash
-git clone https://github.com/ggerganov/llama.cpp
+git clone https://github.com/ggml-org/llama.cpp
 cd llama.cpp
 ```