readme : update Termux instructions (ggerganov#2147)

The file pathing is significant when running models inside of Termux on Android devices. llama.cpp performance is improved with loading a .bin from the $HOME directory.

README.md

@@ -695,7 +695,7 @@ export LD_LIBRARY_PATH=/vendor/lib64:$LD_LIBRARY_PATH
 
 For easy and swift re-execution, consider documenting this final part in a .sh script file. This will enable you to rerun the process with minimal hassle.
 
-Place your desired model into the `/llama.cpp/models/` directory and execute the `./main (...)` script.
+Place your desired model into the `~/llama.cpp/models/` directory and execute the `./main (...)` script.
 
 ### Docker