pkt_sched: Make act_csum depend upon INET.

It uses ip_send_check() and stuff like that.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/Kconfig

@@ -520,7 +520,7 @@ config NET_ACT_SKBEDIT
 
 config NET_ACT_CSUM
         tristate "Checksum Updating"
-        depends on NET_CLS_ACT
+        depends on NET_CLS_ACT && INET
         ---help---
 	  Say Y here to update some common checksum after some direct
 	  packet alterations.