net: Introduce NET_IF_POINTOPOINT flag

This flag can be used by driver to indicate pointopoint links which should
not require destination link address to be resolved.

Jira: ZEP-1656

Change-Id: I58dd3bf48485d6203e75373497e00668317b9825
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
diff --git a/include/net/net_if.h b/include/net/net_if.h
index c3c4d89..2d6be1b 100644
--- a/include/net/net_if.h
+++ b/include/net/net_if.h
@@ -150,6 +150,9 @@
 	/* interface is up/ready to receive and transmit */
 	NET_IF_UP,
 
+	/* interface is pointopoint */
+	NET_IF_POINTOPOINT,
+
 	/* Total number of flags - must be at the end of the enum */
 	NET_IF_NUM_FLAGS
 };