Add missing enum member accept-ra-min-lft to ipv6-devconf.

In commit 1671bcfd76fd ("net: add sysctl accept_ra_min_rtr_lft")
the DEVCONF_* enum was extended with DEVCONF_ACCEPT_RA_MIN_RTR_LFT.

It was renamed to DEVCONF_ACCEPT_RA_MIN_LFT in commit 5027d54a9c30
("net: change accept_ra_min_rtr_lft to affect all RA lifetimes").

Shortly thereafter, this spec was introduced in commit b2f63d904e72
("doc/netlink: Add spec for rt link messages").

This pre-existing issue was detected by Sashiko, when reviewing the
first patch in this series.

Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260824103816.40040-1-ast%40fiberby.net
Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
---
 Documentation/netlink/specs/rt-link.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/netlink/specs/rt-link.yaml b/Documentation/netlink/specs/rt-link.yaml
index 00c915031efd..ab677801cde8 100644
--- a/Documentation/netlink/specs/rt-link.yaml
+++ b/Documentation/netlink/specs/rt-link.yaml
@@ -494,6 +494,8 @@ definitions:
         name: ndisc-evict-nocarrier
       -
         name: accept-untracked-na
+      -
+        name: accept-ra-min-lft
   -
     name: ifla-icmp6-stats
     enum-name:
-- 
2.55.0