[Deps] Retire the CUDA 12 lane (#38404)

Co-authored-by: Mohammad Angkad <mohammad.angkad@radixark.ai>

docker/sgl-deep-ep.Dockerfile

@@ -6,7 +6,6 @@ FROM ${BASE_IMAGE}:cuda${CUDA_VERSION}
 ARG ARCHITECTURE=x86_64
 ARG CUDA_TAG=cu130
 ARG CUDA_VERSION=13.0
-ARG GDRCOPY_VERSION=2.5.1
 ARG NCCL_VERSION=2.30.7
 ARG PYTHON_TAG=cp312-cp312
 ARG TORCH_VERSION=2.13.0
@@ -49,19 +48,6 @@ RUN set -eux; \
     ln -sf "${cuda_stub}" /usr/lib64/libcuda.so; \
     ln -sf "${cuda_stub}" "/usr/lib/${ARCHITECTURE}-linux-gnu/libcuda.so"
 
-# DeepEP v2 uses NCCL Gin on CUDA 13. Keep GDRCopy only for the CUDA 12
-# legacy NVSHMEM/IBGDA build.
-RUN set -eux; \
-    if [ "${CUDA_TAG}" = cu129 ]; then \
-        git clone --depth 1 --branch "v${GDRCOPY_VERSION}" \
-            https://github.com/NVIDIA/gdrcopy.git /opt/gdrcopy; \
-        make -C /opt/gdrcopy CUDA="${CUDA_HOME}" prefix=/usr/local lib_install; \
-        printf '%s\n' /usr/local/lib > /etc/ld.so.conf.d/gdrcopy.conf; \
-        ldconfig; \
-        test -f /usr/local/include/gdrapi.h; \
-        ldconfig -p | grep -q libgdrapi; \
-    fi
-
 RUN --mount=type=cache,id=sgl-deep-ep-pip-${CUDA_TAG}-${PYTHON_TAG}-${ARCHITECTURE},target=/root/.cache/pip \
     set -eux; \
     "${PYTHON_BIN}" -m pip uninstall -y deep-ep sgl-deep-ep || true; \
@@ -69,10 +55,8 @@ RUN --mount=type=cache,id=sgl-deep-ep-pip-${CUDA_TAG}-${PYTHON_TAG}-${ARCHITECTU
     "${PYTHON_BIN}" -m pip install --force-reinstall \
         "torch==${TORCH_VERSION}" \
         --index-url "https://download.pytorch.org/whl/${CUDA_TAG}"; \
-    if [ "${CUDA_TAG}" = cu130 ]; then \
-        "${PYTHON_BIN}" -m pip install --force-reinstall --no-deps \
-            "nvidia-nccl-cu13==${NCCL_VERSION}"; \
-    fi; \
+    "${PYTHON_BIN}" -m pip install --force-reinstall --no-deps \
+        "nvidia-nccl-cu13==${NCCL_VERSION}"; \
     "${PYTHON_BIN}" -m pip install \
         "auditwheel>=6.0" \
         build \