Fixed issue#15359 by adding support of IpaddrToIfIndex MIB

[nmoray]

- What I did
It is an extension PR of PR#284 which is adding support of IpaddressifIndex MIB [OID: OID 1.3.6.1.2.1.4.34.1.3] support.

This will eventually fix the issue#15359.

- How I did it
Added a custom ifindex for docker bridge interface so that get_index_from_str() will return the same for docker0 bridge interface.

- How to verify it

root@sonic:~# show ip int
Interface     Master    IPv4 address/mask    Admin/Oper    BGP Neighbor    Neighbor IP
------------  --------  -------------------  ------------  --------------  -------------
Ethernet0              172.21.227.120/31    up/up         N/A             N/A
Ethernet8              172.21.227.122/31    up/up         N/A             N/A
docker0                 240.127.1.1/24       up/down       N/A             N/A
eth0                    10.4.4.85/23         up/up         N/A             N/A
lo                      127.0.0.1/16         up/up         N/A             N/A

root@sonic:~# ip addr show docker0
5: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default 
    link/ether 02:42:b3:6d:c9:52 brd ff:ff:ff:ff:ff:ff
    inet 240.127.1.1/24 brd 240.127.1.255 scope global docker0
       valid_lft forever preferred_lft forever
    inet6 fd00::1/80 scope global 
       valid_lft forever preferred_lft forever
    inet6 fe80::1/64 scope link 
       valid_lft forever preferred_lft forever

root@sonic:~# ip addr show Bridge
42: Bridge: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 9100 qdisc noqueue state DOWN group default qlen 1000
    link/ether 00:30:64:6a:fa:a3 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::1837:a4ff:fed5:3cfd/64 scope link 
       valid_lft forever preferred_lft forever

root@sonic:/# snmpwalk -v2c -c <comm> localhost 1.3.6.1.2.1.4.34.1.3
iso.3.6.1.2.1.4.34.1.3.1.4.172.21.227.120 = INTEGER: 1
iso.3.6.1.2.1.4.34.1.3.1.4.172.21.227.122 = INTEGER: 9
iso.3.6.1.2.1.4.34.1.3.1.4.10.4.4.85 = INTEGER: 10000
iso.3.6.1.2.1.4.34.1.3.1.4.240.127.1.1 = INTEGER: 4000
iso.3.6.1.2.1.4.34.1.3.1.4.240.127.1.255 = INTEGER: 4000
iso.3.6.1.2.1.4.34.1.3.2.16.253.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1 = INTEGER: 4000
iso.3.6.1.2.1.4.34.1.3.2.16.254.128.0.0.0.0.0.0.0.0.0.0.0.0.0.1 = INTEGER: 4000
iso.3.6.1.2.1.4.34.1.3.2.16.254.128.0.0.0.0.0.0.2.48.100.255.254.106.250.163 = INTEGER: 10000
iso.3.6.1.2.1.4.34.1.3.2.16.254.128.0.0.0.0.0.0.24.55.164.255.254.213.60.253 = INTEGER: 4000

- PR linkage
PR#284