[RFC PATCH netfilter] Fix Unknown symbols in nf_reject_ipvX modules

[Li Zhong <zhong@linux.vnet.ibm.com>]

Commit c8d7b98bec43 moved nf_send_resetX() to modules without module
license, which causes following errors seen on my system: 

[   26.926014] nf_reject_ipv4: Unknown symbol rcu_read_lock_bh_held (err 0)
[   26.926022] nf_reject_ipv4: Unknown symbol rcu_read_lock_held (err 0)
[   26.926030] nf_reject_ipv4: Unknown symbol ip_local_out_sk (err 0)

The code below adds MODULE_LICENSE("GPL") to fix this issue. 

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
---
 net/ipv4/netfilter/nf_reject_ipv4.c | 3 +++
 net/ipv6/netfilter/nf_reject_ipv6.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/net/ipv4/netfilter/nf_reject_ipv4.c b/net/ipv4/netfilter/nf_reject_ipv4.c
index b023b4e..d5df20d 100644
--- a/net/ipv4/netfilter/nf_reject_ipv4.c
+++ b/net/ipv4/netfilter/nf_reject_ipv4.c
@@ -11,6 +11,9 @@
 #include <net/route.h>
 #include <net/dst.h>
 #include <linux/netfilter_ipv4.h>
+#include <linux/module.h>
+
+MODULE_LICENSE("GPL");
 
 /* Send RST reply */
 void nf_send_reset(struct sk_buff *oldskb, int hook)
diff --git a/net/ipv6/netfilter/nf_reject_ipv6.c b/net/ipv6/netfilter/nf_reject_ipv6.c
index 5f5f043..e3e5683 100644
--- a/net/ipv6/netfilter/nf_reject_ipv6.c
+++ b/net/ipv6/netfilter/nf_reject_ipv6.c
@@ -10,6 +10,9 @@
 #include <net/ip6_fib.h>
 #include <net/ip6_checksum.h>
 #include <linux/netfilter_ipv6.h>
+#include <linux/module.h>
+
+MODULE_LICENSE("GPL");
 
 void nf_send_reset6(struct net *net, struct sk_buff *oldskb, int hook)
 {