net/ipv6: fix DEVCONF_ constants

In 3.12 commit e16f5378 (net/ipv6: add
sysctl option accept_ra_min_hop_limit), upstream commit
8013d1d7, we added
DEVCONF_USE_OIF_ADDRS_ONLY and DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT
constants into <linux/ipv6.h>. But they have different values to
upstream because some values were added in upstream and we did not
backport them.

So we have:
        DEVCONF_SUPPRESS_FRAG_NDISC,
+       DEVCONF_USE_OIF_ADDRS_ONLY,
+       DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
        DEVCONF_MAX
And upstream has:
        DEVCONF_SUPPRESS_FRAG_NDISC,
+       DEVCONF_ACCEPT_RA_FROM_LOCAL,
+       DEVCONF_USE_OPTIMISTIC,
+       DEVCONF_ACCEPT_RA_MTU,
+       DEVCONF_STABLE_SECRET,
+       DEVCONF_USE_OIF_ADDRS_ONLY,
+       DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
        DEVCONF_MAX

Now, our DEVCONF_USE_OIF_ADDRS_ONLY corresponds to
DEVCONF_USE_OIF_ADDRS_ONLY-4 == DEVCONF_ACCEPT_RA_FROM_LOCAL from
upstream. Similarly the other constant.

Fix that by simply defining the missing constants to make the values
equal.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Cc: Luis Henriques <luis.henriques@canonical.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hangbin Liu <liuhangbin@gmail.com>

include/uapi/linux/ipv6.h

@@ -163,6 +163,10 @@ enum {
 	DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL,
 	DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL,
 	DEVCONF_SUPPRESS_FRAG_NDISC,
+	DEVCONF_ACCEPT_RA_FROM_LOCAL,
+	DEVCONF_USE_OPTIMISTIC,
+	DEVCONF_ACCEPT_RA_MTU,
+	DEVCONF_STABLE_SECRET,
 	DEVCONF_USE_OIF_ADDRS_ONLY,
 	DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
 	DEVCONF_MAX