Register CPU CI for 17 e2e tests and partition xeon base-c suite (#35227)

Co-authored-by: Zhang, Mingxu <mingxu.zhang@intel.com>
Co-authored-by: MingxuZh <109504044+MingxuZh@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>

docker/xeon.Dockerfile

@@ -39,7 +39,7 @@ RUN source /opt/.venv/bin/activate && \
     git checkout ${VER_SGLANG} && \
     cd python && \
     cp pyproject_cpu.toml pyproject.toml && \
-    uv pip install . && \
+    uv pip install ".[diffusion]" && \
     cd sglang/kernels/aot && \
     cp pyproject_cpu.toml pyproject.toml && \
     uv pip install . && \