selftests/seccomp: use 90s as timeout

selftests/seccomp: use 90s as timeout

As seccomp_benchmark tries to calibrate how many samples will take more
than 5 seconds to execute, it may end up picking up a number of samples
that take 10 (but up to 12) seconds. As the calibration will take double
that time, it takes around 20 seconds. Then, it executes the whole thing
again, and then once more, with some added overhead. So, the thing might
take more than 40 seconds, which is too close to the 45s timeout.

That is very dependent on the system where it's executed, so may not be
observed always, but it has been observed on x86 VMs. Using a 90s timeout
seems safe enough.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Link: https://lore.kernel.org/r/20200601123202.1183526-1-cascardo@canonical.com
Signed-off-by: Kees Cook <keescook@chromium.org>