[Bug]: test_config_fec_oper_mode doesn't handle port with FEC mode None

[bingwang-ms]

Issue Description

There are two issues in this test

1. The test test_config_fec_oper_mode is failing on some testbeds because the FEC mode is set to none for some ports. Setting the FEC mode to rs will bring the port down.

admin@str-msn2700-22:~$ show int status
     Interface            Lanes    Speed    MTU    FEC    Alias            Vlan    Oper    Admin             Type    Asym PFC
--------------  ---------------  -------  -----  -----  -------  --------------  ------  -------  ---------------  ----------
    Ethernet24      24,25,26,27     100G   9100   none     etp7           trunk      up       up  QSFP28 or later         off
    Ethernet28      28,29,30,31     100G   9100   none     etp8           trunk      up       up  QSFP28 or later         off
    Ethernet32      32,33,34,35     100G   9100   none     etp9           trunk      up       up  QSFP28 or later         off
    Ethernet36      36,37,38,39     100G   9100   none    etp10           trunk      up       up  QSFP28 or later         off

2. The wait_until is not working properly. Test is not failing even if the port is not up. Please add an assert to check the result of wait_until.
   

   sonic-mgmt/tests/platform_tests/test_intf_fec.py

   Line 90 in 5c2245a

   wait_until(30, 2, 0, duthost.is_interface_status_up, intf["interface"])

Results you see

Test failed on some testbeds.

Results you expected to see

Test should pass.

Is it platform specific

generic

Relevant log output

No response

Output of show version

No response

Attach files (if any)

No response

[bingwang-ms]

@vvolam, @prgeor Can you help take a look?

[vvolam]

PRs to fix the issue are merged.