[Doc] Add Cambricon MLU support (vllm-project#25942)

Signed-off-by: a120092009 <zhaoty0121@gmail.com>
Signed-off-by: xuebwang-amd <xuebwang@amd.com>

Author: a120092009

docs/getting_started/installation/README.md

@@ -25,3 +25,4 @@ The backends below live **outside** the main `vllm` repository and follow the
 | MetaX MACA GPU | N/A, install from source | <https://github.com/MetaX-MACA/vLLM-metax> |
 | Rebellions ATOM / REBEL NPU | `vllm-rbln` | <https://github.com/rebellions-sw/vllm-rbln> |
 | IBM Spyre AIU | `vllm-spyre` | <https://github.com/vllm-project/vllm-spyre> |
+| Cambricon MLU | `vllm-mlu` | <https://github.com/Cambricon/vllm-mlu> |