SCA: Add IAR C-STAT support

[felipe-iar]

This PR adds IAR C-STAT support in the Zephyr Static Code Analysis (SCA) framework.

Reference: <LANG>_ICSTAT

CC: @danielfl-iar, @micaelbo, @RobinKastberg

[github-actions]

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[Copilot]

Pull Request Overview

This PR adds IAR C-STAT static code analysis tool support to the Zephyr Static Code Analysis (SCA) framework. IAR C-STAT is a comprehensive static analysis tool for C/C++ source code that can find errors and vulnerabilities while supporting various coding standards.

• Adds a new SCA variant for IAR C-STAT that integrates with the existing Zephyr SCA framework
• Provides configurable analysis parameters including rulesets, threading, and database options
• Creates documentation explaining installation, usage, and configuration options

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
doc/develop/sca/index.rst	Adds IAR to the list of supported SCA tools
doc/develop/sca/iar.rst	Complete documentation for IAR C-STAT integration including installation, usage, and configuration
cmake/sca/iar/sca.cmake	CMake implementation that configures IAR C-STAT with customizable parameters and integrates with CMake's ICSTAT support

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[pdgendt]

Is there an example of how the output looks?

[sonarqubecloud]

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

See analysis details on SonarQube Cloud