Bazel: simplified bazelrc config

tools/apollo.bazelrc.sample

 build --action_env CUDA_TOOLKIT_PATH="/usr/local/cuda-10.2"
-build --action_env TF_CUDA_COMPUTE_CAPABILITIES="6.0,6.1,7.0,7.2,7.5"
+build --action_env TF_CUDA_COMPUTE_CAPABILITIES="5.2,6.0,6.1,7.0,7.2,7.5"
 
 build --action_env PYTHON_BIN_PATH="/usr/bin/python3"
 build --action_env PYTHON_LIB_PATH="/usr/lib/python3/dist-packages"
@@ -8,8 +8,6 @@ build --python_path="/usr/bin/python3"
 build:gpu --config=cuda
 build:gpu --config=tensorrt
 
-#build:gpu --action_env USE_GPU=1
-
 ## The following was adapted from tensorflow/.bazelrc
 
 # This config refers to building with CUDA available. It does not necessarily