If for any reason you need to uninstall F-Secure Linux Security, the documented procedure is as follows:

You can uninstall the product with the uninstall-fsav command-line command.

Run the following script as root user to uninstall the product: /opt/f-secure/fsav/bin/uninstall-fsav

The uninstall script does not remove configuration files. If you are sure that you do not need them anymore, remove all files in the /etc/opt/f-secure/fsma path.

It should be noted that the installation of current versions of F-Secure Linux Security do not require you to uninstall the previous version unless you are running a version earlier than 10.x.  If you are running version earlier than 10.x, the current kit will not install and will tell you to uninstall the earlier version first.