[qca-nss-ecm] Do not create interface instance with zero MAC address.

Change-Id: Ic495c9c03e66df8c1f003d4f18e803099ca1366e
Signed-off-by: Murat Sezgin <msezgin@codeaurora.org>
diff --git a/ecm_interface.c b/ecm_interface.c
index 9942980..29cb015 100644
--- a/ecm_interface.c
+++ b/ecm_interface.c
@@ -2043,6 +2043,14 @@
 	if (dev_type == ARPHRD_ETHER) {
 
 		/*
+		 * If MAC address is zeros, do nothing.
+		 */
+		if (is_zero_ether_addr(dev->dev_addr)) {
+			DEBUG_WARN("Net device %p MAC address is all zeros\n", dev);
+			return NULL;
+		}
+
+		/*
 		 * Ethernet - but what sub type?
 		 */