[cherry-pick] add head file for memcpy (#3653) add pip, python-dev (#3655) (#3656)

docs/user_guides/source_compile.md

@@ -156,7 +156,7 @@ wget -c https://mms-res.cdn.bcebos.com/cmake-3.10.3-Linux-x86_64.tar.gz && \
 
 ###### 编译环境要求
 
-- gcc、g++、git、make、wget、python、patchelf
+- gcc、g++、git、make、wget、python、pip、python-dev、patchelf
 - cmake（建议使用3.10或以上版本）
 
 ###### 具体步骤
@@ -167,7 +167,7 @@ wget -c https://mms-res.cdn.bcebos.com/cmake-3.10.3-Linux-x86_64.tar.gz && \
 # 1. Install basic software
 apt update
 apt-get install -y --no-install-recomends \
-  gcc g++ make wget python unzip
+  gcc g++ make wget python unzip patchelf python-dev
 
 # 2. install cmake 3.10 or above
 wget https://www.cmake.org/files/v3.10/cmake-3.10.3.tar.gz

lite/utils/cv/paddle_image_preprocess.cc

@@ -14,6 +14,7 @@
 
 #include "lite/utils/cv/paddle_image_preprocess.h"
 #include <math.h>
+#include <string.h>
 #include <algorithm>
 #include <climits>
 #include "lite/utils/cv/image2tensor.h"