[NPU] Qwen2 divide linear in decode layers

[cyita]

Description

Qwen2 divide linear in decode layers.
Usage:

set IPEX_LLM_N_SPLITS_LINEAR=14
set IPEX_LLM_N_SPLITS_DOWN_PROJ=8

TODOs:

• Solve conflicts
• Use ruonan's sequence_concat + reduce sum

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
  - ...