You have downloaded the source to compile ntop.
Adding own binaries to SPLAT is not supported and I really can understand this (even i miss some tools).
The best you can make now is cleanup the system ;)
Code:
cd /home/admin/
rm -rf ntop
btw.
ntop is a nice tool but if you look at the depend list you will know why it is not best practice for security to have it at a firewall.