[DOC] [BACKEND] Add klx support in readme

Author: zhzhcookie

README.md

@@ -35,6 +35,7 @@ python3 -m pip install . --no-build-isolation -v
 ```shell
 # xpu (klx)
 # Recommended: Use the Docker image (22GB) https://su.bcebos.com/klx-sdk-release-public/xpytorch/docker/ubuntu2004_v030/ubuntu_2004_x86_64_v30.tar
+# Contact kunlunxin-support@baidu.com for support
 mkdir -p ~/.flagtree/xpu; cd ~/.flagtree/xpu
 wget https://github.com/FlagTree/flagtree/releases/download/v0.1.0-build-deps/XTDK-llvm19-ubuntu2004_x86_64.tar.gz
 wget https://github.com/FlagTree/flagtree/releases/download/v0.1.0-build-deps/xre-Linux-x86_64.tar.gz

README_cn.md

@@ -35,6 +35,7 @@ python3 -m pip install . --no-build-isolation -v
 ```shell
 # xpu (klx)
 # 推荐使用镜像（22GB）https://su.bcebos.com/klx-sdk-release-public/xpytorch/docker/ubuntu2004_v030/ubuntu_2004_x86_64_v30.tar
+# 联系 kunlunxin-support@baidu.com 可获取进一步支持
 mkdir -p ~/.flagtree/xpu; cd ~/.flagtree/xpu
 wget https://github.com/FlagTree/flagtree/releases/download/v0.1.0-build-deps/XTDK-llvm19-ubuntu2004_x86_64.tar.gz
 wget https://github.com/FlagTree/flagtree/releases/download/v0.1.0-build-deps/xre-Linux-x86_64.tar.gz