fix potential race condition (ABA) in the dist_fifo's steal method
fix potential race condition (ABA) in the dist_fifo's steal method

marioskogias/libfiber,brianwatling/libfiber,marioskogias/libfiber,brianwatling/libfiber,marioskogias/libfiber,marioskogias/libfiber,brianwatling/libfiber,brianwatling/libfiber