[NET_SCHED]: Add mask support to fwmark classifier

Support masking the nfmark value before the search. The mask value is
global for all filters contained in one instance. It can only be set
when a new instance is created, all filters must specify the same mask.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/pkt_cls.h b/include/linux/pkt_cls.h
index bd2c5a2..c3f01b3 100644
--- a/include/linux/pkt_cls.h
+++ b/include/linux/pkt_cls.h
@@ -305,6 +305,7 @@
 	TCA_FW_POLICE,
 	TCA_FW_INDEV, /*  used by CONFIG_NET_CLS_IND */
 	TCA_FW_ACT, /* used by CONFIG_NET_CLS_ACT */
+	TCA_FW_MASK,
 	__TCA_FW_MAX
 };