selftests: forwarding: Allow to get netdev interfaces names from commandline

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/forwarding/lib.sh

@@ -45,6 +45,21 @@ if [[ ! -v NUM_NETIFS ]]; then
 	exit 0
 fi
 
+##############################################################################
+# Command line options handling
+
+count=0
+
+while [[ $# -gt 0 ]]; do
+	if [[ "$count" -eq "0" ]]; then
+		unset NETIFS
+		declare -A NETIFS
+	fi
+	count=$((count + 1))
+	NETIFS[p$count]="$1"
+	shift
+done
+
 ##############################################################################
 # Network interfaces configuration