Allow sensor value override in mfg mode only

Issue: User is able to override sensor value even though system is not
in manufacturing mode

Fix: Code changes are done to patch sensor values when system is only
in manufacturing Mode.

Tested:
1. Redfish validator - passed for this new change

Case 1:
1. Enable manufacturing mode by pressing power button while bmc booting
2. Patch sensor values from Redfish.
Redfish URI:
PATCH https://<BMC-IP>/redfish/v1/Chassis/WC_Baseboard/Thermal
Body:
{
    "Temperatures": [
    {
        "MemberId": "SSB_Temp",
        "ReadingCelsius":112
    }
]
}

Response:
{
  "@odata.id": "/redfish/v1/Chassis/WC_Baseboard/Thermal",
  "@odata.type": "#Thermal.v1_4_0.Thermal",
  "Fans": [],
  "Id": "Thermal",
  "Name": "Thermal",
  "Temperatures": []
}

3. Sensor value Overridden successfully

Case 2: Varified for ValidationUnsecure mode.
Case 3: Tested without SpecialMode mode
1. Stop the specialmodemgr.service service
2. Patch sensor values from Redfish.
3. Sensor value Overridden successfully

Case 4:
1. Disable manufacturing mode
Command: ipmitool raw 0x30 0xB4 3 0
Response:            //Success
2. Patch sensor values from Redfish.
Redfish URI:
PATCH https://<BMC-IP

>/redfish/v1/Chassis/WC_Baseboard/Thermal
Body:
{
    "Temperatures": [
    {
        "MemberId": "SSB_Temp",
        "ReadingCelsius":112
    }
]
}

3. Returning proper error.
Response :
{
  "error": {
    "@Message.ExtendedInfo": [
      {
        "@odata.type": "/redfish/v1/$metadata#Message.v1_0_0.Message",
        "Message": "The action Overriding of Sensor Value for
            non manufacturing mode is not supported by the resource.",
        "MessageArgs": [
          "Overriding of Sensor Value for non manufacturing mode"
        ],
        "MessageId": "Base.1.4.0.ActionNotSupported",
        "Resolution": "The action supplied cannot be resubmitted to
           the implementation.  Perhaps the action was invalid, the
           wrong resource was the target or the implementation
           documentation may be of assistance.",
        "Severity": "Critical"
      }
    ],
    "code": "Base.1.4.0.ActionNotSupported",
    "message": "The action Overriding of Sensor Value for
            non manufacturing mode is not supported by the resource."
  }
}

Signed-off-by: jayaprakash Mutyala <mutyalax.jayaprakash@intel.com>
Change-Id: I34cd53fba939fb367310c531a050792ef749dd70