config load_minigraph broken on Mellanox-SN2700-D40C8S8

[qiluo-msft]

Description

Steps to reproduce the issue:

1. Install a recent built master image https://dev.azure.com/mssonic/build/_build/results?buildId=42496&view=results
2. run command lines as below

admin@str-msn2700-20:~$ show ver
SONiC Software Version: SONiC.master.42496-32e73b087
Distribution: Debian 10.11
Kernel: 4.19.0-12-2-amd64
Build commit: 32e73b087
Build date: Sat Oct  9 23:17:38 UTC 2021
Built by: AzDevOps@sonic-build-workers-000S2B

Platform: x86_64-mlnx_msn2700-r0
HwSKU: Mellanox-SN2700-D40C8S8
ASIC: mellanox
ASIC Count: 1
Serial Number: MT2028X35361
Model Number: MSN2700-CS2FO
Hardware Revision: A2
Uptime: 04:01:49 up 11 min,  1 user,  load average: 1.32, 1.58, 1.16
Docker images:
REPOSITORY                    TAG                      IMAGE ID            SIZE
docker-syncd-mlnx             latest                   d038b3eacc97        1.03GB
docker-syncd-mlnx             master.42496-32e73b087   d038b3eacc97        1.03GB
docker-platform-monitor       latest                   72624a3c1ba5        744MB
docker-platform-monitor       master.42496-32e73b087   72624a3c1ba5        744MB
docker-snmp                   latest                   387e5d702b49        490MB
docker-snmp                   master.42496-32e73b087   387e5d702b49        490MB
docker-teamd                  latest                   3760974089f8        460MB
docker-teamd                  master.42496-32e73b087   3760974089f8        460MB
docker-nat                    latest                   f3619e7f5882        429MB
docker-nat                    master.42496-32e73b087   f3619e7f5882        429MB
docker-macsec                 latest                   aa6fdf9503b4        429MB
docker-macsec                 master.42496-32e73b087   aa6fdf9503b4        429MB
docker-lldp                   latest                   d752e8f13fc5        454MB
docker-lldp                   master.42496-32e73b087   d752e8f13fc5        454MB
docker-database               latest                   e2e105c1840c        414MB
docker-database               master.42496-32e73b087   e2e105c1840c        414MB
docker-orchagent              latest                   ebc0cd9d5d47        444MB
docker-orchagent              master.42496-32e73b087   ebc0cd9d5d47        444MB
docker-sonic-telemetry        latest                   fdb625d5c09b        502MB
docker-sonic-telemetry        master.42496-32e73b087   fdb625d5c09b        502MB
docker-sonic-mgmt-framework   latest                   5025d2cd1cb1        569MB
docker-sonic-mgmt-framework   master.42496-32e73b087   5025d2cd1cb1        569MB
docker-sflow                  latest                   3d3966b4486f        427MB
docker-sflow                  master.42496-32e73b087   3d3966b4486f        427MB
docker-router-advertiser      latest                   9fe0610a40a0        414MB
docker-router-advertiser      master.42496-32e73b087   9fe0610a40a0        414MB
docker-fpm-frr                latest                   c69f55bb7cf5        449MB
docker-fpm-frr                master.42496-32e73b087   c69f55bb7cf5        449MB
docker-dhcp-relay             latest                   dcc6a4594dcd        427MB

admin@str-msn2700-20:~$ sudo config load_minigraph
Reload config from minigraph? [y/N]: y
Disabling container monitoring ...
Stopping SONiC target ...
Running command: /usr/local/bin/sonic-cfggen -H -m -j /etc/sonic/init_cfg.json   --write-to-db
Traceback (most recent call last):
  File "/usr/local/bin/sonic-cfggen", line 441, in <module>
    main()
  File "/usr/local/bin/sonic-cfggen", line 335, in main
    deep_update(data, parse_xml(minigraph, platform, asic_name=asic_name))
  File "/usr/local/lib/python3.7/dist-packages/minigraph.py", line 1221, in parse_xml
    (ports, alias_map, alias_asic_map) = get_port_config(hwsku=hwsku, platform=platform, port_config_file=port_config_file, asic_name=asic_name, hwsku_config_file=hwsku_config_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 134, in get_port_config
    return parse_platform_json_file(hwsku_json_file, port_config_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 278, in parse_platform_json_file
    child_ports = get_child_ports(intf, brkout_mode, platform_json_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 228, in get_child_ports
    alias_list = port_dict[INTF_KEY][interface]['breakout_modes'][breakout_mode]
KeyError: '1x10G'

admin@str-msn2700-20:~$ sonic-cfggen -H -m  --print-data
Traceback (most recent call last):
  File "/usr/local/bin/sonic-cfggen", line 441, in <module>
    main()
  File "/usr/local/bin/sonic-cfggen", line 335, in main
    deep_update(data, parse_xml(minigraph, platform, asic_name=asic_name))
  File "/usr/local/lib/python3.7/dist-packages/minigraph.py", line 1221, in parse_xml
    (ports, alias_map, alias_asic_map) = get_port_config(hwsku=hwsku, platform=platform, port_config_file=port_config_file, asic_name=asic_name, hwsku_config_file=hwsku_config_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 134, in get_port_config
    return parse_platform_json_file(hwsku_json_file, port_config_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 278, in parse_platform_json_file
    child_ports = get_child_ports(intf, brkout_mode, platform_json_file)
  File "/usr/local/lib/python3.7/dist-packages/portconfig.py", line 228, in get_child_ports
    alias_list = port_dict[INTF_KEY][interface]['breakout_modes'][breakout_mode]
KeyError: '1x10G'

Describe the results you received:

Describe the results you expected:

Output of show version:

master.42496-32e73b087

Output of show techsupport:

(paste your output here or download and attach the file here )

Additional information you deem important (e.g. issue happens only occasionally):

[qiluo-msft]

It is fixed by #8953