Revert "blocklist-helper: Silence a bogus pf warning"

This reverts commit 2347ca2.

A fix has been implemented in 99560fe ("pfctl: Do not warn if there
is no Ethernet anchor").

Revert this commit to avoid having differences with upstream.

MFC after:	2 days

Author: jlduran

contrib/blocklist/libexec/blocklistd-helper

@@ -258,7 +258,7 @@ flush)
 	pf)
 		# dynamically determine which anchors exist
 		for anchor in $(/sbin/pfctl -a "$2" -s Anchors 2> /dev/null); do
-			/sbin/pfctl -a "$anchor" -t "port${anchor##*/}" -T flush 2> /dev/null
+			/sbin/pfctl -a "$anchor" -t "port${anchor##*/}" -T flush
 			/sbin/pfctl -a "$anchor" -F rules
 		done
 		echo OK

libexec/blocklistd-helper/blacklistd-helper

@@ -279,7 +279,7 @@ flush)
 	pf)
 		# dynamically determine which anchors exist
 		for anchor in $(/sbin/pfctl -a "$2" -s Anchors 2> /dev/null); do
-			/sbin/pfctl -a "$anchor" -t "port${anchor##*/}" -T flush 2> /dev/null
+			/sbin/pfctl -a "$anchor" -t "port${anchor##*/}" -T flush
 			/sbin/pfctl -a "$anchor" -F rules
 		done
 		echo OK