…asses (sonic-net#82)

Previous commit to transition to importing sonic-py-common accidentally replaced all `logger` instances in xcvrd with `self`, although not all of these instances resided in the `DaemonXcvrd` class, breaking them. Here we add a global Logger instance for these references to use. Eventually we should refactor so that there is only one Logger instance created by xcvrd, not two.

- Also rename class names using PascalCase for consistency across the codebase.
- Also add Logger instance to ThermalMonitor class in thermalctld

…et#82)

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#### Description
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The DOM and Status related APIs need to be modified to ensure that the fields which have latched registers are moved to the flag specific API.
Also, all the VDM specific fields have now been removed from DOM and Status related APIs since separate APIs pertaining to processing VDM data have now been created.

This change is in line to the requirements of [SONiC/doc/platform_api/CMIS_Diagnostic_Monitoring_Overview_in_SONiC.md at master · sonic-net/SONiC](https://github.com/sonic-net/SONiC/blob/master/doc/platform_api/CMIS_Diagnostic_Monitoring_Overview_in_SONiC.md)

#### Motivation and Context
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N/A

#### How Has This Been Tested?
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Please refer to sonic-net/sonic-utilities#3844 for the test details

#### Additional Information (Optional)
MSFT ADO - 30090754

Related PRs
sonic-net/SONiC#1954
sonic-net/sonic-platform-daemons#604
sonic-net/sonic-utilities#3844