Fix SEC_STAT.IRM bit handling in ARC SEM interrupt entry/exit

[vishwamartur]

Related to #331

Fix the Memory Read Protection Violation from Secure MPU exception on exit from interrupt.

• Add code to store SEC_STAT.IRM bit in INTERRUPT_PROLOGUE macro.
• Add code to restore SEC_STAT.IRM bit in INTERRUPT_EPILOGUE macro.
• Modify portable/ThirdParty/GCC/ARC_EM_HS/arc_support.s to include the changes in the interrupt entry/exit macros.

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[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[ActoryOu]

Hi @vishwamartur, Thanks for your contribution again! Could you help share your verfication result?

[aggarg]

@vishwamartur Would you please share how you tested these changes?

[aggarg]

@vishwamartur Would you please share the testing details.

[vishwamartur]

Hi @ActoryOu and @aggarg,

Thank you for reviewing the PR. I haven’t yet tested the changes. I'll perform the required tests to verify the SEC_STAT.IRM bit handling in the interrupt entry/exit macros and will update the PR with the results shortly.

Please let me know if there are specific scenarios you'd like me to cover in the testing process.

Best regards,
Vishwa

[aggarg]

I am closing this PR. Please open a new one when you have tested the changes.