Finalize CMake setup for OSLib project

[dogo]

Summary

This PR finalizes and refines the CMake-based build system for the OSLib project, ensuring a reliable and maintainable setup tailored for PSP development. Key configurations and enhancements have been implemented to streamline the build process and improve cross-compilation support.

Key Changes

• CMake Configuration:

  • Introduced a modular CMake setup, defining the libosl.a static library as the main output.
  • All relevant source files and directories are correctly included, with specific handling for assembly files.
  • Ensured that the .a file is outputted directly in the project root directory.

• PSP Toolchain Integration:

  • Created and utilized a Platform/PSP.cmake file to manage PSP-specific toolchain settings.
  • Configured the C and C++ compilers, assembler, and common PSP compilation flags within the platform file.

• Build Process:

  • Established a straightforward build process involving psp-cmake .. and make commands.
  • Verified successful builds with the correct output directory and file naming conventions.

Improvements:

• Cross-Compilation Support: Enhanced the PSP toolchain integration for better cross-compilation, centralizing PSP-specific configurations.
• Maintainability: The project is now easier to maintain, with a clear separation of platform-specific configurations and project-specific build logic.

Testing and Validation:

• Successfully tested the build process, confirming that the libosl.a static library is correctly generated in the root directory.
• Verified that all source files are compiled with the appropriate flags, and the output is as expected.