feat(Examples): Add Ref Trim procedure to MAX32690 ADC Example

[BrentK-ADI]

feat(Examples): Add Ref Trim procedure to MAX32690 ADC Example

Description

Adds functions to the MAX32690 ADC example project to perform the reference trim for all ADC reference sources.

Checklist Before Requesting Review

• [X] PR Title follows correct guidelines.
• [X] Description of changes and all other relevant information.
• [ ] (Optional) Link any related GitHub issues using a keyword
• [ ] (Optional) Provide info on any relevant functional testing/validation. For API changes or significant features, this is not optional.

[BrentK-ADI]

Force push to cf70915 was to resolve cpplint and clang-format errors.

[BrentK-ADI]

Added comments to trim functions calling out the UG.