samples: ocpp: add native_sim configuration

Disable DHCPv4 and use static network configuration
for native_sim board

Signed-off-by: Muhammad Waleed Badar <walid.badar@gmail.com>

Author: walidbadar

samples/net/ocpp/boards/native_sim.conf

@@ -0,0 +1,7 @@
+# Network address config
+CONFIG_NET_DHCPV4=n
+CONFIG_NET_CONFIG_SETTINGS=y
+CONFIG_NET_CONFIG_NEED_IPV4=y
+CONFIG_NET_CONFIG_MY_IPV4_ADDR="192.0.2.1"
+CONFIG_NET_CONFIG_PEER_IPV4_ADDR="192.0.2.2"
+CONFIG_NET_CONFIG_MY_IPV4_GW="192.0.2.2"