Fixed: warnings "deprecated conversion from string constant to 'char*' [-Wwrite-strings]" generated by g++.

src/util/learn_prepare.cpp

@@ -16,9 +16,9 @@
 using namespace easypr;
 
 //! 将以下路径改成你的位置
-char * notlabelPath = "F:/data/easypr-data/notlabel";
-char * hasPaltePath = "F:/data/easypr-data/learn/hasPlate/";
-char * noPlatePath = "F:/data/easypr-data/learn/noPlate/";
+const char * notlabelPath = "F:/data/easypr-data/notlabel";
+const char * hasPaltePath = "F:/data/easypr-data/learn/hasPlate/";
+const char * noPlatePath = "F:/data/easypr-data/learn/noPlate/";
 
 //! 读取not label data，生成learn data
 void label_data()

src/util/mc_data_prepare.cpp

@@ -242,7 +242,7 @@ void getLearnData()
 void changeFileName()
 {
     //char * filePath = "F:/data/easypr-data/learndata";
-    char * filePath = "F:/data/PlateLocate/pic1";
+    const char * filePath = "F:/data/PlateLocate/pic1";
     
     ////获取该路径下的所有文件
     auto files = Utils::getFiles(filePath);