Update custom_op doc (#1572) (#1573)

doc/fluid/advanced_usage/development/new_op/custom_op.md

@@ -251,29 +251,25 @@ lib_dir=$( python -c 'import paddle; print(paddle.sysconfig.get_lib())' )
 echo $include_dir
 echo $lib_dir
 
+# PaddlePaddel >=1.6.1, 仅需要include ${include_dir} 和 ${include_dir}/third_party
 nvcc relu_op.cu -c -o relu_op.cu.o -ccbin cc -DPADDLE_WITH_CUDA -DEIGEN_USE_GPU -DPADDLE_USE_DSO -Xcompiler -fPIC -std=c++11 -Xcompiler -fPIC -w --expt-relaxed-constexpr -O3 -DNVCC \
-    -I ${include_dir}/third_party/install/gflags/include \
-    -I ${include_dir}/third_party/install/glog/include \
-    -I ${include_dir}/third_party/install/protobuf/include \
-    -I ${include_dir}/third_party/install/xxhash/include \
-    -I ${include_dir}/third_party/boost \
-    -I ${include_dir}/third_party/eigen3 \
-    -I ${include_dir}/third_party/dlpack/include \
-    -I ${include_dir}/third_party/threadpool/src/extern_threadpool \
     -I ${include_dir} \
+    -I ${include_dir}/third_party \
 
 g++ relu_op.cc relu_op.cu.o -o relu2_op.so -shared -fPIC -std=c++11 -O3 \
-  -I ${include_dir}/third_party/install/protobuf/include \
-  -I ${include_dir}/third_party/install/glog/include \
-  -I ${include_dir}/third_party/install/gflags/include \
-  -I ${include_dir}/third_party/install/xxhash/include \
-  -I ${include_dir}/third_party/install/zlib/include \
-  -I ${include_dir}/third_party/boost \
-  -I ${include_dir}/third_party/eigen3 \
-  -I ${include_dir}/third_party/dlpack/include \
   -I ${include_dir} \
+  -I ${include_dir}/third_party \
   -L /usr/local/cuda/lib64 \
   -L ${lib_dir} -lpaddle_framework -lcudart
+
+# PaddlePaddel 1.6.0, 需要include的third_party如下:
+#  -I ${include_dir}/third_party/install/protobuf/include \
+#  -I ${include_dir}/third_party/install/glog/include \
+#  -I ${include_dir}/third_party/install/gflags/include \
+#  -I ${include_dir}/third_party/install/xxhash/include \
+#  -I ${include_dir}/third_party/boost \
+#  -I ${include_dir}/third_party/eigen3 \
+#  -I ${include_dir}/third_party/dlpack/include \
 ```