USE flag 'pax_kernel' to be renamed to 'pax-kernel' - 28/06/2021 00:00 GMT

On 2021-07-01 the USE flag 'pax_kernel' will be renamed to 'pax-kernel'
in order to remove the disallowed underscore character. If you use
a PaX-enabled kernel, update your package-manager configuration
accordingly; failure to do so might result in affected packages no longer
functioning on your system.