[Suggestion] In multiple systems, the login guide option displays ubuntukylin or other more recognizable names

[CrossCC]

Version：20.04LTS
ISO：ubuntukylin-20.04-050803-amd64.iso
Test environment：Lenovo ThinkPad-X1-Yoga

Test steps:

1. The low version of UKUI has been installed, and other systems such as Windows and Fedora have been installed
2. When installing the 0508 version, there is no option to "uninstall Ubuntu20.04 and reinstall", resulting in two UKUI boot options after installation. The new installation only displays Ubuntu, and the old version displays Ubuntu 20.04 LTS (20.04) (in ... partition)

Whether the boot option needs to display Ubuntukylin is more recognizable.

[CrossCC]

测试步骤：
1、已安装过低版本UKUI，并且有安装Windows、Fedora等其他系统
2、再安装0508版本时没有“卸载Ubuntu20.04并重新安装”的选项，导致安装后有两个UKUI的引导选项，新安装的只显示Ubuntu，旧版本的显示Ubuntu 20.04 LTS（20.04）（在...分区）

引导选项是否需要显示Ubuntukylin，更有辨识度。

[liuyuanpeng176]

不是登录的bug