错误信息如下：
E: /var/cache/apt/archives/linux-image-2.6.24-19-generic_2.6.24-19.41_i386.deb: unable to make backup link of `./boot/vmlinuz-2.6.24-19-generic' before installing new version
E: /var/cache/apt/archives/linux-image-2.6.24-23-generic_2.6.24-23.48_i386.deb: unable to make backup link of `./boot/vmlinuz-2.6.24-23-generic' before installing new version
