Add TI Arm Clang Compiler Support to Core Tests

[smmasongt]

Builds on previous work in CMSIS-Toolbox to add TI Arm Clang Compiler support to CMSIS under designator CLANG_TI.

• Adds Clang_TI option to Core Unit Tests scripts.
• Adds new Cortex-R device selections to Core Unit Tests scripts.
• Updates documentation to include new compiler and devices.
• Fixes link issue with Clang Compiler 20.1.0 which pointed to 404 website. Moved link from LLVM Embedded Toolchain to new Arm Toolchain for Embedded repo.

Note: Cortex-R support is dependent on pull request #45 and future header updates.

[JonatanAntoni]

@smmasongt, you may want to discuss distributing your toolchain via vcpkg like we do. This would make it easier for users to install the toolchain properly.

[smmasongt]

@JonatanAntoni I'll work on removing those unnecessary dependencies tonight. I misunderstood the build flow and thought the toolchain environment variables were used indirectly by CMSIS Toolbox.

[smmasongt]

@smmasongt, you may want to discuss distributing your toolchain via vcpkg like we do. This would make it easier for users to install the toolchain properly.

I'll reach out to the Arm maintainers to see if they would be willing to add it to vcpkg. I'm not affiliated with TI so hopefully there won't be any license issues with rehosting the installers.

[JonatanAntoni]

I'll reach out to the Arm maintainers to see if they would be willing to add it to vcpkg. I'm not affiliated with TI so hopefully there won't be any license issues with rehosting the installers.

Ah, thanks for stating this clear. TI would be expected to run their own vcpkg registry. Re-hosting would not be required once the download links are public. Its just a matter of providing some json metadata files which point to the download links and give some installation instructions (such as the CLANG_TI_TOOLCHAIN_5_0_0 environment variable).

[JonatanAntoni]

@smmasongt, please check the conflicts we got. And consider enhancing the GitHub workflow in core.yml to install the TI Compiler like documented.