Add Hard Fault handler for Cortex-M0

[antoniofagundes]

Description

• Add Hard Fault handler for Cortex-M0.
• Add if/defs to coexist with current handler for M3&M4 cores.
• Add test code for hard fault.

Motivation and Context

• Need to improve hard fault debugging for Cortex-M0 core.

How Has This Been Tested?

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: António Fagundesantonio.fagundes@eclo.solutions

[nfbot]

Hi @antoniofagundes,

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Thank you for your contribution!

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