Keep changelogs in minimized builds for native deb pkgs

Debian changelog.Debian.* files are already keept for minimized
builds. But those changelogs are from non-native .deb packages (see
man dh_installchangelogs). Native .deb packages name their changelog
just changelog.* . So keep them in a minimized build, too.

LP: #1943114

live-build/auto/build

@@ -188,8 +188,8 @@ path-exclude=/usr/share/doc/*
 # ... except copyright files ...
 path-include=/usr/share/doc/*/copyright
 
-# ... and Debian changelogs
+# ... and Debian changelogs for native & non-native packages
-path-include=/usr/share/doc/*/changelog.Debian.*
+path-include=/usr/share/doc/*/changelog.*
 EOF
 
 		# Remove docs installed by bootstrap