net_if: begin fixing issues

- it may happen that net_if_up is never called on iface inside of the
  begin function, forcing it if the netif is not up
- it may happen that the dhcpv4 address is already bound before the wait
  for the event is started, avoid that as it may be reported as an error
- removed wait forever in dhcp wait event listener in favor of 10s which
  seems enough in order to report the error to the user and let him
  start the retrial procedure

Author: andreagilardoni

libraries/SocketWrapper/SocketHelpers.cpp

@@ -100,15 +100,22 @@ void NetworkInterface::setMACAddress(const uint8_t *mac) {
 }
 
 int NetworkInterface::begin(bool blocking, uint64_t additional_event_mask) {
+	if (!net_if_is_up(netif)) {
+		net_if_up(netif);
+	}
+
 	dhcp();
 
 	// FIXME: additional_event_mask cannot be ORed here due to how Zephyr
 	// events are handled internally. Must be reworked to wait on a sem
 	// and register multiple event masks with event_handler instead.
 	ARG_UNUSED(additional_event_mask);
 
-	int ret = net_mgmt_event_wait_on_iface(netif, NET_EVENT_IPV4_ADDR_ADD, NULL, NULL, NULL,
-										   blocking ? K_FOREVER : K_SECONDS(1));
+	int ret = 0;
+	if (blocking && netif->config.dhcpv4.state != NET_DHCPV4_BOUND) {
+		ret = net_mgmt_event_wait_on_iface(netif, NET_EVENT_IPV4_DHCP_BOUND, NULL, NULL, NULL,
+										   K_SECONDS(10));
+	}
 	return (ret == 0) ? 1 : 0;
 }