ubuntu-drivers-common should avoid "distro-provided-script error" message from be shown in NVIDIA upstream driver installer when no "Ubuntu's nvidia packages" are installed in the system.

[Ｖ字龍(Vdragon)]

Currently NVIDIA's upstream installer will emit a "The distribution-provided pre-install script failed! Are you sure you want to continue?" message when /usr/lib/nvidia/pre-install script returns error (which is hard-coded to always return 1 no matter that ubuntu-provided NVIDIA proprietary driver exist or not), logics should be implemented from letting NVIDIA proprietary installer display that confusing message to the user when the system is free of ubuntu-supplied NVIDIA proprietary drivers.

`````````` /var/log/nvidia-installer.log `````````
-> Running distribution scripts
   executing: '/usr/lib/nvidia/pre-install'...
-> done.
-> The distribution-provided pre-install script failed! Are you sure you want to continue? (Answer: Continue installation)

```````````````````````````````````````````````

``````````` /usr/lib/nvidia/pre-install ```````
#!/bin/sh

# Trigger an error exit status to prevent the installer from overwriting
# Ubuntu's nvidia packages.

exit 1
```````````````````````````````````````````````