This change makes busybox aware of both connman and the standard dhcp
client, while there is a caveat about using busybox's ifup/ifdown, this
change will make the 3 possibly dhcp clients behave better when busybox
is used.
Enable the CONFIG_FEATURE_IFUPDOWN_EXTERNAL_DHCP feature to busybox will
search for various external clients and then add connman as an external
client.
[YOCTO #6521]
Signed-off-by: Saul Wold <sgw@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
