Remove Out of tree Driver from GPU driver installation document

[qiyuangong]

Description

GPU drivers are already upstreamed to Kernel 6.2+. Remove the out-of-tree driver (intel-i915-dkms) for 6.2-6.5. https://dgpu-docs.intel.com/driver/kernel-driver-types.html#gpu-driver-support

1. Why the change?

2. User API changes

3. Summary of the change

4. How to test?

• N/A
• Unit test: Please manually trigger the PR Validation here by inputting the PR number (e.g., 1234). And paste your action link here once it has been successfully finished.
• Application test
• Document test
• ...

5. New dependencies

• New Python dependencies
  - Dependency1
  - Dependency2
  - ...
• New Java/Scala dependencies and their license
  - Dependency1 and license1
  - Dependency2 and license2
  - ...

[liu-shaojun]

LGTM

[Oscilloscope98]

No need to update the contents in readthedocs anymore :）
Besides, should we also update this file? https://github.com/intel-analytics/ipex-llm/blob/main/docs/mddocs/Overview/install_gpu.md

[qiyuangong]

No need to update the contents in readthedocs anymore :） Besides, should we also update this file? https://github.com/intel-analytics/ipex-llm/blob/main/docs/mddocs/Overview/install_gpu.md

In install_gpu.md, we recommended intel-i915-dkms for performance. That's reasonable.