Use "--extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/ " for IPEX package installation

[ywang30intel]

Use "--extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/ "
instead of "-f https://developer.intel.com/ipex-whl-stable-xpu"
in the instruction guide for bigdl-llm installation.
IPEX installation instructions: https://intel.github.io/intel-extension-for-pytorch/xpu/latest/tutorials/installations/linux.html
for generic python:
python -m pip install torch==2.0.1a0 torchvision==0.15.2a0 intel_extension_for_pytorch==2.0.110+xpu --extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/

The "-f" may not work. I got bunch of errors in one of IDC system with following command:
pip install --pre --upgrade bigdl-llm[xpu] -f https://developer.intel.com/ipex-whl-stable-xpu
This is due to the "-f https://developer.intel.com/ipex-whl-stable-xpu" not working and the right torch and IPEX package can't be found from that link.
Use
pip install --pre --upgrade bigdl-llm[xpu] --extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/
can solve the issue.

[hkvision]

@rnwang04 Shall we update to this command?

[rnwang04]

@ywang30intel Thanks for suggestion!
@hkvision I will do some validation first.

[rnwang04]

--extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/ doesn't work at our local machine. Maybe it just works for some special cases or proxy?

I prefer to keep using current -f https://developer.intel.com/ipex-whl-stable-xpu, maybe we can add --extra-index-url https://pytorch-extension.intel.com/release-whl/stable/xpu/us/ into our doc as a backup. @hkvision

[hkvision]

I agree. Good idea.