libxcb bundles all extension libraries in the main package instead of splitting them into subpackages, preventing proper dependency detection during builds.

[vejeta]

Problem

libxcb bundles all extension libraries in the main package instead of splitting them into subpackages, preventing proper dependency detection during builds.

Impact

• Qt5 configure cannot detect libxcb-glx during build, silently disabling GLX support
• Other build systems expecting granular XCB packages fail dependency checks
• Breaks compatibility with standard packaging practices from Alpine/Debian

Proposed solution

Split libxcb extensions into subpackages following Alpine/Debian patterns:

• libxcb-glx (for GLX extension)
• libxcb-render
• libxcb-shm
• libxcb-xfixes
• libxcb-randr
• etc.

The main libxcb package should depend on all subpackages for backward compatibility.

Testing

Working implementation in PR https://github.com/wolfi-dev/os/pull/69098/files that fixes Qt5 OpenGL support.