samples: net: irc_bot: add DHCPv4 support

When CONFIG_NET_DHCPV4 is selected, ignore the CONFIG_NET_SAMPLES_MY_IPV4_ADDR
setting and instead used DHCPv4.

NOTE: This commit also adds a placeholder for DHCPv6 behavior which is not
yet functional.

Change-Id: Id31fcb99be46e966babf18f94b5dec151920dedc
Signed-off-by: Michael Scott <michael.scott@linaro.org>
3 files changed