Revert "TT#44917 Ship certain modules only on Debian/stretch"

This reverts commit 039086e505.

The are modules not adapted for the new version of prosody shipping with buster
(0.11), so we have to keep using prosody 0.9 from stretch until this is sorted
out.

Thus reverting the commit, with a minor adaptation for another change that
creates a conflict (switching dependencies from debhelper>=10 to
debhelper-compat=12).

Change-Id: I6abd1e81dd432f4f1033c85490a232f0a0675412
(cherry picked from commit 5c9c26594c)

debian/control

@@ -6,7 +6,6 @@ Homepage: https://www.sipwise.com/
 Standards-Version: 3.9.8
 Build-Depends:
  debhelper-compat (= 12),
- lsb-release,
  quilt,
 
 Package: ngcp-prosody-modules

debian/rules

@@ -15,17 +15,6 @@ override_dh_auto_configure:
 override_dh_install:
 	dh_install
 	find debian/ngcp-prosody-modules/ -name README.\* -delete
-	# conflicts with prosody >=0.10.2-1 in Debian/buster
-	if lsb_release -rs | grep -q '^9' ; then \
-		echo "Keeping all modules for Debian stretch"; \
-	else \
-		echo "Removing conflicting modules (shipped by prosody in Debian)"; \
-		find debian/ngcp-prosody-modules/ -name fallback_archive.lib.lua -delete; \
-		find debian/ngcp-prosody-modules/ -name mamprefs.lib.lua -delete; \
-		find debian/ngcp-prosody-modules/ -name mamprefsxml.lib.lua -delete; \
-		find debian/ngcp-prosody-modules/ -name mod_mam.lua -delete; \
-		find debian/ngcp-prosody-modules/ -name mod_websocket.lua -delete; \
-	fi
 
 override_dh_auto_clean:
 	rm -f debian/README_mod_*.*