It looks as though the installation was interrupted in an earlier session.
Try sudo apt-get install -f to see if it will fix broken dependencies.
If that fails, purge MySQL server:
sudo apt-get purge mysql-community-server mysql-community-server
Then clean and update:
sudo apt-get autoclean && sudo apt-get clean && sudo apt-get update
Do a general upgrade:
sudo apt-get upgrade
Now try re-installing:
sudo apt-get install mysql-server and mysql-community-server
If you are doing this from the root prompt, then you don't lead the leading sudo command.
