ipv6: improve ipv6_find_hdr() to skip empty routing headers

This patch prepares ipv6_find_hdr() function so that it could be
able to skip routing headers, where segements_left is 0. This is
required to handle multiple routing header case correctly when
changing IPv6 addresses.

Signed-off-by: Ansis Atteka <aatteka@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index b2f0cfb..acbd8e0 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -631,8 +631,9 @@
 extern bool			ipv6_ext_hdr(u8 nexthdr);
 
 enum {
-	IP6_FH_F_FRAG	= (1 << 0),
-	IP6_FH_F_AUTH	= (1 << 1),
+	IP6_FH_F_FRAG		= (1 << 0),
+	IP6_FH_F_AUTH		= (1 << 1),
+	IP6_FH_F_SKIP_RH	= (1 << 2),
 };
 
 /* find specified header and get offset to it */