!15336 fix read input issue

From: @zhujingxuan
Reviewed-by: @hangangqiang,@wangchengyuan
Signed-off-by: @hangangqiang

mindspore/lite/micro/coder/generator/component/const_blocks/load_input.cc

@@ -84,7 +84,7 @@ void *ReadInputData(const char *real_input_path, int *size) {
   }
   if (strstr(real_input_path, ".bin") || strstr(real_input_path, ".net")) {
     FILE *file;
-    file = fopen(real_input_path, "rb+");
+    file = fopen(real_input_path, "rb");
     if (!file) {
       printf("Can't find %s\n", real_input_path);
       return NULL;