Don't use deprecated Lintian flag --fail-on-warnings

This flag has been deprecated without replacement upstream back in 2016.
https://lists.debian.org/debian-lint-maint/2016/12/msg00017.html

Change-Id: Icb6de5af033cc8e335bd5ec1ae64fa99eeae0213
diff --git a/packages.mk b/packages.mk
index 4ff2c86..a0e2ca2 100644
--- a/packages.mk
+++ b/packages.mk
@@ -112,7 +112,7 @@
 	$(LOG) $1 pbuilder pdebuild
 	cd $(PRODUCT_OUT)/obj/$1; pdebuild \
 		--buildresult $(PRODUCT_OUT)/packages/$(if $6,$6,core) -- \
-		--debbuildopts "--build=$(if $5,$5,full) -sa --check-command=lintian --check-option=--fail-on-warnings --check-option=--profile=mendel" \
+		--debbuildopts "--build=$(if $5,$5,full) -sa --check-command=lintian --check-option=--profile=mendel" \
 		--basetgz $(ROOTDIR)/cache/$(if $7,$7,cross)-base.tgz \
 		--configfile $(ROOTDIR)/build/pbuilderrc \
 		--hookdir $(ROOTDIR)/build/pbuilder-hooks \
diff --git a/setup.sh b/setup.sh
index 65df7fa..af58ca0 100755
--- a/setup.sh
+++ b/setup.sh
@@ -103,7 +103,7 @@
     dpkg-buildpackage -tc -us -ui -uc
 
     echo; echo ===== lintian run below =====
-    lintian --include-dir=$ROOTDIR/build/lintian --fail-on-warnings --profile=mendel
+    lintian --include-dir=$ROOTDIR/build/lintian --profile=mendel
     local exitcode=$?
 
     popd >/dev/null