[IPV6]: ADDRCONF: Add accept_ra_pinfo sysctl.

This controls whether we accept Prefix Information in RAs.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index c5131a0..2c3b7994 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -146,6 +146,7 @@
 #endif
 	__s32		max_addresses;
 	__s32		accept_ra_defrtr;
+	__s32		accept_ra_pinfo;
 	void		*sysctl;
 };
 
@@ -169,6 +170,7 @@
 	DEVCONF_MAX_ADDRESSES,
 	DEVCONF_FORCE_MLD_VERSION,
 	DEVCONF_ACCEPT_RA_DEFRTR,
+	DEVCONF_ACCEPT_RA_PINFO,
 	DEVCONF_MAX
 };