Function format_vulkan_version 

pub fn format_vulkan_version(packed: u32) -> String

Decode a packed Vulkan version into major.minor.patch.

Vulkan packs the version as variant:3 | major:7 | minor:10 | patch:12. The variant field is deliberately ignored: it is non-zero only for non-Khronos derivatives, and including it would print a leading number no user recognises.