[NETFILTER]: x_tables: replace IPv4 dscp match by address family independent version

This replaces IPv4 dscp match by address family independent version.
This also
	- utilizes dsfield.h to get the DS field in IPv4/IPv6 header, and
	- checks for the DSCP value from user space.
	- fixes Kconfig help text.

Signed-off-by: Yasuyuki Kozakai <[email protected]>
Signed-off-by: Patrick McHardy <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 6fa4b75..0b8a70c 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -37,6 +37,7 @@
 obj-$(CONFIG_NETFILTER_XT_MATCH_CONNMARK) += xt_connmark.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_CONNTRACK) += xt_conntrack.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_DCCP) += xt_dccp.o
+obj-$(CONFIG_NETFILTER_XT_MATCH_DSCP) += xt_dscp.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_ESP) += xt_esp.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_HELPER) += xt_helper.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_LENGTH) += xt_length.o