libcudnn.so.7 is not a symbolic link

当出现/sbin/ldconfig.real: /usr/local/cuda/lib64/libcudnn.so.7 is not a symbolic link错误时，如upgrade出现错误：

upgrade error.png

1. check the link:

sudo ldconfig -v

sudo ldconfig -v.png

2. Find the error:
   /usr/local/cuda/lib64/libcudnn.so.7 is not a symbolic link
   libcudnn.so.7 -> libcudnn.so.7.0.5

3. Create the new link manually:
   sudo ln -sf /usr/local/cuda/lib64/libcudnn.so.7.0.5 /usr/local/cuda/lib64/libcudnn.so.7

参考：libcudnn.so.7 is not a symbolic link