improvement(dockerfile): use make -j$(nporc) when build ncnn (#840)

* use make -j$(nporc) when build ncnn

* improve cpu dockerfile

docker/CPU/Dockerfile

@@ -68,10 +68,13 @@ RUN git clone https://github.com/Tencent/ncnn.git &&\
     git submodule update --init &&\
     mkdir -p build && cd build &&\
     cmake -DNCNN_VULKAN=OFF -DNCNN_SYSTEM_GLSLANG=ON -DNCNN_BUILD_EXAMPLES=ON -DNCNN_PYTHON=ON -DNCNN_BUILD_TOOLS=ON -DNCNN_BUILD_BENCHMARK=ON -DNCNN_BUILD_TESTS=ON .. &&\
+    make -j$(nproc) &&\
     make install &&\
     cd /root/workspace/ncnn/python &&\
     pip install -e .
 
+ENV PATH="/root/workspace/ncnn/build/tools/quantize/:${PATH}"
+
 ### install mmdeploy
 WORKDIR /root/workspace
 ARG VERSION