gcov: Add gcov gcc implementation and toolchain to ci compilation

[W-M-R]

Summary

When running qemu/nsh_smp or sim/nsh configuration, run gcov -d /tmp/xxx to save all gcov generated data and export them to the host. Use ./tools/gcov.sh to parse and generate reports. For details, see: Documentation/applications/system/gcov/index.rst

Impact

Update this section, where applicable, on how change affects users,
build process, hardware, documentation, security, compatibility, etc.

Testing

When running qemu/nsh_smp or sim/nsh configuration, run gcov -d /tmp/xxx to save all gcov generated data and export them to the host. Use ./tools/gcov.sh to parse and generate reports. For details, see: Documentation/applications/system/gcov/index.rst

[nuttxpr]

[Experimental Bot, please feedback here]

This PR does not fully meet the NuttX requirements as presented. While it provides a summary of the change and some testing information, it is missing crucial details.

Here's a breakdown of what's missing and how to improve it:

Summary:

• Missing Clarity on Necessity: The summary states why gcov data is being saved and exported, but not why this change is necessary. Was gcov data not accessible before? Was it difficult to access? Was the previous method unreliable? This needs clarification.
• Functional Part: The summary mentions tools and configurations affected, but not the specific code files or modules changed. e.g., "Changes were made to the NSH builtin commands and the qemu/sim configurations."
• Exact Mechanism: The summary describes the user-facing steps but not how the code achieves this. Does it involve new NSH commands? Modifications to existing code? New configuration options?

Impact:

• The impact section is completely unaddressed. This is a major deficiency. The PR author must consider and document the impact on users (do they need new commands? different workflow?), build process (new dependencies?), hardware (any specific requirements?), documentation (updated to reflect the new feature?), security (does exporting this data pose any risks?), compatibility (does this break anything existing?), and any other considerations. Even if the answer is "NO" for each, it must be explicitly stated.

Testing:

• Insufficient Test Logs: Simply stating how to run the tests is not enough. Actual output from the tests before and after the change is required. This allows reviewers to see the difference and verify the functionality. The current text describes how to test, not the results of testing.
• Limited Testing Scope: While testing on qemu/nsh_smp and sim/nsh is mentioned, are there other configurations where this change might have an impact that should be tested?
• Missing Build Host Information: The PR must specify the development environment used for testing, including the OS, CPU architecture, and compiler version.

Example of an improved summary:

"This change adds support for easily exporting gcov data from qemu/nsh_smp and sim/nsh configurations. Previously, accessing gcov data from these configurations required manual intervention and was prone to errors. This change introduces a new NSH command 'gcov_export' and modifies the qemu and sim startup scripts to automatically save gcov data to a specified location. This data can then be processed using the existing tools/gcov.sh script. This addresses issue #[Insert Issue Number Here]".

By addressing these missing points, the PR will significantly improve in quality and make it easier for reviewers to understand and approve the changes.

[W-M-R]

Sorry, the configuration of qemu64 is turned on incorrectly. I will make the necessary changes later.