graphics/vulkan-extension-layer: update to 1.4.326
While here, correct license and add LICENSE_FILE.
Changelog: https://github.com/KhronosGroup/Vulkan-ExtensionLayer/compare/v1.4.321...v1.4.326
PR: 289833
Approved by: Atanu Biswas <atanubiswas484@gmail.com> (maintainer)