[IPV6]: Fix sending extension headers before and including routing header.

Based on suggestion from Masahide Nakamura <nakam@linux-ipv6.org>.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 65ec866..53c76c8 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -237,6 +237,8 @@
 						   int newtype,
 						   struct ipv6_opt_hdr __user *newopt,
 						   int newoptlen);
+struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
+					  struct ipv6_txoptions *opt);
 
 extern int ip6_frag_nqueues;
 extern atomic_t ip6_frag_mem;