Coding Guidelines: Resolve the issues under Rule 21.2

[yerabolu]

Describe the bug
Code should be compliant with the Rule 21.2 - A reserved identifier or reserved macro name shall not be declared
https://docs.zephyrproject.org/latest/guides/coding_guidelines/index.html?highlight=guidelines

Also refer to the discussion in RFC #32590

To Reproduce
Static analysis scans with enabled coding guideline checkers will show all the issues.

Expected behavior
Code should be compliant with the rule.

Additional context
Code should be compliant with the rules for Functional Safety

[nashif]

we should not have bugs/enhancements for each coding guideline, this is unmanageable, This is a project direction and should be tracked in the tools we use, not here.