[action] [PR:15688] [FRR] Fixing the advertisement of static ipv6 route

[mssonicbld]

Why I did it

To fix an issue - FRRouting/frr#13587

Work item tracking

• Microsoft ADO (number only):

How I did it

Ported a fix from FRR - FRRouting/frr#13875

How to verify it

Deploy image on T0, verify that Loopback IPv6 network is advertised to arista:

ARISTA01T1>show ipv6 route fc00:1::

VRF: default
Routing entry for fc00:1::
Codes: C - connected, S - static, K - kernel, O3 - OSPFv3, B - BGP, R - RIP, A B - BGP Aggregate, I L1 - IS-IS level 1, I L2 - IS-IS level 2, DH - DHCP, NG - Nexthop Group Static Route, M
- Martian, DP - Dynamic Policy Route, L - VRF Leaked, RC - Route Cache Route

 B fc00:1::/64 [200/0]
 via fc00::1, Port-Channel1

ARISTA01T1>ping fc00:1::32
PING fc00:1::32(fc00:1::32) 72 data bytes
80 bytes from fc00:1::32: icmp_seq=1 ttl=64 time=1.54 ms
80 bytes from fc00:1::32: icmp_seq=2 ttl=64 time=1.11 ms
80 bytes from fc00:1::32: icmp_seq=3 ttl=64 time=1.17 ms
80 bytes from fc00:1::32: icmp_seq=4 ttl=64 time=1.17 ms
80 bytes from fc00:1::32: icmp_seq=5 ttl=64 time=1.18 ms

--- fc00:1::32 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 5ms
rtt min/avg/max/mdev = 1.117/1.241/1.547/0.155 ms, ipg/ewma 1.428/1.390 ms

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111
• 202205
• 202211
• 202305

Tested branch (Please provide the tested image version)

Description for the changelog

Link to config_db schema for YANG module changes

A picture of a cute animal (not mandatory but encouraged)

[mssonicbld]

Original PR: #15688