Our NTP package definition fetches source from the HTTP-only URL 
http://archive.ntp.org/.

This redirects to an HTTPS URL, https://www.eecis.udel.edu.

Then, the whole things fails because GnuTLS is not available. So, patch
1/2 adds the eecis.udel.edu URL so that GnuTLS is provided.

udel.edu is the University of Delaware, where the NTP inventor David
Mills is a professor emeritus:
https://www.eecis.udel.edu/~mills/ntp.html

Your thoughts?