Fixup the regex used for iptables so it actually works

make/iptables.mk

@@ -15,9 +15,8 @@ $(IPTABLES_BUILD_DIR)/.unpacked: $(DL_DIR)/$(IPTABLES_SOURCE)
 	touch $(IPTABLES_BUILD_DIR)/.unpacked
 
 $(IPTABLES_BUILD_DIR)/.configured: $(IPTABLES_BUILD_DIR)/.unpacked
-	$(SED) "s@shell.*YES.*@shell grep -q '__UCLIBC_HAS_IPV6__.*1' \
-		$(BUILD_DIR)/uClibc/include/bits/uClibc_config.h && \
-		echo YES\), YES\)@;" $(IPTABLES_BUILD_DIR)/Makefile
+	$(SED) "s;\[ -f /usr/include/netinet/ip6.h \];grep -q '__UCLIBC_HAS_IPV6__ 1' \
+		$(BUILD_DIR)/uClibc/include/bits/uClibc_config.h;" $(IPTABLES_BUILD_DIR)/Makefile
 	touch  $(IPTABLES_BUILD_DIR)/.configured
 
 $(IPTABLES_BUILD_DIR)/iptables: $(IPTABLES_BUILD_DIR)/.configured