If build fails because of failed experimental check and stdout is
redirected to /dev/null, it is absolutely unclear why build fails.
Fixes: a4bcd61de82d ("buildtools: add script to check experimental API exports")
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>