[CMake] Post install scripts for debian

[as]

Hello:

We are using CMake to create inhouse deb packages for our project. We
need to run a script after installing the package: postinst script
which is possible in Debian. I don't know how to enable this from
CMake - do I set some flags? Do I just put the file in a particular
location? I'm not able to find much help on the web.

Any help will be appreciated.

Thanks,
Aravind.