iproute2: Add iptables PACKAGECONFIG knob

iproute2 detects presence of iptables during building and can also
be built without it. Add PACKAGECONFIG option which allows user to
optionally leave it out, and enable it by default to keep current
recipe behavior.

(From OE-Core rev: 07ddaeaacaab4c3e264816dea6de32378617bf4e)

Signed-off-by: Niko Mauno <niko.mauno@vaisala.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/iproute2/iproute2_6.13.0.bb

@@ -9,7 +9,7 @@ LICENSE = "GPL-2.0-or-later"
 LIC_FILES_CHKSUM = "file://COPYING;md5=eb723b61539feef013de476e68b5c50a \
                     "
 
-DEPENDS = "flex-native bison-native iptables libcap"
+DEPENDS = "flex-native bison-native libcap"
 
 SRC_URI = "${KERNELORG_MIRROR}/linux/utils/net/${BPN}/${BP}.tar.xz \
            file://0001-include-libnetlink.h-add-missing-include-for-htobe64.patch \
@@ -19,10 +19,11 @@ SRC_URI[sha256sum] = "a43aa43338d882b44d01e549f3f105a92ae9feea32a82fae45a88e7a49
 
 inherit update-alternatives bash-completion pkgconfig
 
-PACKAGECONFIG ??= "tipc elf devlink"
+PACKAGECONFIG ??= "tipc elf devlink iptables"
 PACKAGECONFIG[tipc] = ",,libmnl,"
 PACKAGECONFIG[elf] = ",,elfutils,"
 PACKAGECONFIG[devlink] = ",,libmnl,"
+PACKAGECONFIG[iptables] = ",,iptables"
 PACKAGECONFIG[rdma] = ",,libmnl,"
 PACKAGECONFIG[selinux] = ",,libselinux"