Fix CUDA_HOME env var

Author: djherbis

Dockerfile.tmpl

@@ -202,7 +202,7 @@ ENV GIT_COMMIT=${GIT_COMMIT} \
 RUN echo "$GIT_COMMIT" > /etc/git_commit && echo "$BUILD_DATE" > /etc/build_date
 
 {{ if eq .Accelerator "gpu" }}
-    # Add the CUDA home.
-    CUDA_HOME=/usr/local/cuda
+# Add the CUDA home.
+ENV CUDA_HOME=/usr/local/cuda
 {{ end }}
 ENTRYPOINT ["/usr/bin/env"]