[WideEP] Remove pplx all2all backend (#33724)

Signed-off-by: Tyler Michael Smith <tlrmchlsmth@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

tools/ep_kernels/install_python_libraries.sh

@@ -4,12 +4,10 @@ set -ex
 # usage: ./install_python_libraries.sh [options]
 #   --workspace <dir>    workspace directory (default: ./ep_kernels_workspace)
 #   --mode <mode>        "install" (default) or "wheel"
-#   --pplx-ref <commit>  pplx-kernels commit hash
 #   --deepep-ref <commit> DeepEP commit hash
 #   --nvshmem-ver <ver>  NVSHMEM version 
 
 CUDA_HOME=${CUDA_HOME:-/usr/local/cuda}
-PPLX_COMMIT_HASH=${PPLX_COMMIT_HASH:-"12cecfd"}
 DEEPEP_COMMIT_HASH=${DEEPEP_COMMIT_HASH:-"73b6ea4"}
 NVSHMEM_VER=${NVSHMEM_VER:-"3.3.24"}  # Default supports both CUDA 12 and 13
 WORKSPACE=${WORKSPACE:-$(pwd)/ep_kernels_workspace}
@@ -35,14 +33,6 @@ while [[ $# -gt 0 ]]; do
             MODE="$2"
             shift 2
             ;;
-        --pplx-ref)
-            if [[ -z "$2" || "$2" =~ ^- ]]; then
-                echo "Error: --pplx-ref requires an argument." >&2
-                exit 1
-            fi
-            PPLX_COMMIT_HASH="$2"
-            shift 2
-            ;;
         --deepep-ref)
             if [[ -z "$2" || "$2" =~ ^- ]]; then
                 echo "Error: --deepep-ref requires an argument." >&2
@@ -188,14 +178,6 @@ do_build() {
     popd
 }
 
-# build pplx-kernels
-do_build \
-    "https://github.com/ppl-ai/pplx-kernels" \
-    "pplx-kernels" \
-    "setup.py" \
-    "$PPLX_COMMIT_HASH" \
-    ""
-
 # build DeepEP
 do_build \
     "https://github.com/deepseek-ai/DeepEP" \