It appears they have changed the port name very recently. We will need to update the paparazzi-tools port to depend on git instead of git-core.
As a temporary fix, you can manually edit the paparazzi-tools port file to install git instead of git core.
Clean the halted install:
$ sudo port clean paparazzi-tools
Edit the port file:
$ sudo port edit paparazzi-tools
Change this line:
and save the file.
Then try to install the port again:
$ sudo port install paparazzi-tools
If you do this, the next time you do port selfupdate, it will reset the port file back to the original, so you would have to edit it again (I think).
Note I have not actually tested this, but it should work (been a while since I was playing around with macports though). If you want to update the port in paparazzi-portability-support and submit a pull request, awesome! Let me know if this doesn't work.