The feature mesa[lavapipe] provides the lavapipe software Vulkan driver.
To use the driver, first add <vcpkg_installed>/bin to PATH, then point the Vulkan loader at the installed ICD manifest:
    VK_DRIVER_FILES=<vcpkg_installed>/share/vulkan/icd.d/lvp_icd.json
(replaces driver discovery) or
    VK_ADD_DRIVER_FILES=<vcpkg_installed>/share/vulkan/icd.d/lvp_icd.json
(adds lavapipe to the normal driver search).
